Delete rtc::Callback0 and friends.

Replaced with std::function.

Bug: webrtc:6424
Change-Id: Iacc43822cb854ddde3cb1e5ddd863676cb07510a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/205005
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Tommi <tommi@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33281}

common_video/include/video_frame_buffer.h

@@ -12,10 +12,10 @@
 #define COMMON_VIDEO_INCLUDE_VIDEO_FRAME_BUFFER_H_
 
 #include <stdint.h>
+#include <functional>
 
 #include "api/scoped_refptr.h"
 #include "api/video/video_frame_buffer.h"
-#include "rtc_base/callback.h"
 #include "rtc_base/ref_counted_object.h"
 
 namespace webrtc {
@@ -29,7 +29,7 @@ rtc::scoped_refptr<I420BufferInterface> WrapI420Buffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used);
+    std::function<void()> no_longer_used);
 
 rtc::scoped_refptr<I444BufferInterface> WrapI444Buffer(
     int width,
@@ -40,7 +40,7 @@ rtc::scoped_refptr<I444BufferInterface> WrapI444Buffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used);
+    std::function<void()> no_longer_used);
 
 rtc::scoped_refptr<I420ABufferInterface> WrapI420ABuffer(
     int width,
@@ -53,7 +53,7 @@ rtc::scoped_refptr<I420ABufferInterface> WrapI420ABuffer(
     int v_stride,
     const uint8_t* a_plane,
     int a_stride,
-    const rtc::Callback0<void>& no_longer_used);
+    std::function<void()> no_longer_used);
 
 rtc::scoped_refptr<PlanarYuvBuffer> WrapYuvBuffer(
     VideoFrameBuffer::Type type,
@@ -65,7 +65,7 @@ rtc::scoped_refptr<PlanarYuvBuffer> WrapYuvBuffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used);
+    std::function<void()> no_longer_used);
 
 rtc::scoped_refptr<I010BufferInterface> WrapI010Buffer(
     int width,
@@ -76,7 +76,7 @@ rtc::scoped_refptr<I010BufferInterface> WrapI010Buffer(
     int u_stride,
     const uint16_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used);
+    std::function<void()> no_longer_used);
 
 }  // namespace webrtc
 

common_video/video_frame_buffer.cc

@@ -30,7 +30,7 @@ class WrappedYuvBuffer : public Base {
                    int u_stride,
                    const uint8_t* v_plane,
                    int v_stride,
-                   const rtc::Callback0<void>& no_longer_used)
+                   std::function<void()> no_longer_used)
       : width_(width),
         height_(height),
         y_plane_(y_plane),
@@ -70,7 +70,7 @@ class WrappedYuvBuffer : public Base {
   const int y_stride_;
   const int u_stride_;
   const int v_stride_;
-  rtc::Callback0<void> no_longer_used_cb_;
+  std::function<void()> no_longer_used_cb_;
 };
 
 // Template to implement a wrapped buffer for a I4??BufferInterface.
@@ -87,7 +87,7 @@ class WrappedYuvaBuffer : public WrappedYuvBuffer<BaseWithA> {
                     int v_stride,
                     const uint8_t* a_plane,
                     int a_stride,
-                    const rtc::Callback0<void>& no_longer_used)
+                    std::function<void()> no_longer_used)
       : WrappedYuvBuffer<BaseWithA>(width,
                                     height,
                                     y_plane,
@@ -136,7 +136,7 @@ class WrappedYuv16BBuffer : public Base {
                       int u_stride,
                       const uint16_t* v_plane,
                       int v_stride,
-                      const rtc::Callback0<void>& no_longer_used)
+                      std::function<void()> no_longer_used)
       : width_(width),
         height_(height),
         y_plane_(y_plane),
@@ -176,7 +176,7 @@ class WrappedYuv16BBuffer : public Base {
   const int y_stride_;
   const int u_stride_;
   const int v_stride_;
-  rtc::Callback0<void> no_longer_used_cb_;
+  std::function<void()> no_longer_used_cb_;
 };
 
 class I010BufferBase : public I010BufferInterface {
@@ -206,7 +206,7 @@ rtc::scoped_refptr<I420BufferInterface> WrapI420Buffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used) {
+    std::function<void()> no_longer_used) {
   return rtc::scoped_refptr<I420BufferInterface>(
       new rtc::RefCountedObject<WrappedYuvBuffer<I420BufferInterface>>(
           width, height, y_plane, y_stride, u_plane, u_stride, v_plane,
@@ -224,7 +224,7 @@ rtc::scoped_refptr<I420ABufferInterface> WrapI420ABuffer(
     int v_stride,
     const uint8_t* a_plane,
     int a_stride,
-    const rtc::Callback0<void>& no_longer_used) {
+    std::function<void()> no_longer_used) {
   return rtc::scoped_refptr<I420ABufferInterface>(
       new rtc::RefCountedObject<WrappedYuvaBuffer<I420ABufferInterface>>(
           width, height, y_plane, y_stride, u_plane, u_stride, v_plane,
@@ -240,7 +240,7 @@ rtc::scoped_refptr<I444BufferInterface> WrapI444Buffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used) {
+    std::function<void()> no_longer_used) {
   return rtc::scoped_refptr<I444BufferInterface>(
       new rtc::RefCountedObject<WrappedYuvBuffer<I444BufferBase>>(
           width, height, y_plane, y_stride, u_plane, u_stride, v_plane,
@@ -257,7 +257,7 @@ rtc::scoped_refptr<PlanarYuvBuffer> WrapYuvBuffer(
     int u_stride,
     const uint8_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used) {
+    std::function<void()> no_longer_used) {
   switch (type) {
     case VideoFrameBuffer::Type::kI420:
       return WrapI420Buffer(width, height, y_plane, y_stride, u_plane, u_stride,
@@ -279,7 +279,7 @@ rtc::scoped_refptr<I010BufferInterface> WrapI010Buffer(
     int u_stride,
     const uint16_t* v_plane,
     int v_stride,
-    const rtc::Callback0<void>& no_longer_used) {
+    std::function<void()> no_longer_used) {
   return rtc::scoped_refptr<I010BufferInterface>(
       new rtc::RefCountedObject<WrappedYuv16BBuffer<I010BufferBase>>(
           width, height, y_plane, y_stride, u_plane, u_stride, v_plane,

media/base/media_channel.h

@@ -43,7 +43,6 @@
 #include "modules/rtp_rtcp/include/report_block_data.h"
 #include "rtc_base/async_packet_socket.h"
 #include "rtc_base/buffer.h"
-#include "rtc_base/callback.h"
 #include "rtc_base/copy_on_write_buffer.h"
 #include "rtc_base/dscp.h"
 #include "rtc_base/logging.h"

modules/video_coding/codecs/h264/h264_decoder_impl.cc

@@ -32,7 +32,6 @@ extern "C" {
 #include "common_video/include/video_frame_buffer.h"
 #include "modules/video_coding/codecs/h264/h264_color_space.h"
 #include "rtc_base/checks.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/logging.h"
 #include "system_wrappers/include/field_trial.h"
 #include "system_wrappers/include/metrics.h"
@@ -302,8 +301,9 @@ int32_t H264DecoderImpl::Decode(const EncodedImage& input_image,
   VideoFrame* input_frame =
       static_cast<VideoFrame*>(av_buffer_get_opaque(av_frame_->buf[0]));
   RTC_DCHECK(input_frame);
-  const webrtc::I420BufferInterface* i420_buffer =
+  rtc::scoped_refptr<VideoFrameBuffer> frame_buffer =
-      input_frame->video_frame_buffer()->GetI420();
+      input_frame->video_frame_buffer();
+  const webrtc::I420BufferInterface* i420_buffer = frame_buffer->GetI420();
 
   // When needed, FFmpeg applies cropping by moving plane pointers and adjusting
   // frame width/height. Ensure that cropped buffers lie within the allocated
@@ -330,7 +330,9 @@ int32_t H264DecoderImpl::Decode(const EncodedImage& input_image,
       av_frame_->width, av_frame_->height, av_frame_->data[kYPlaneIndex],
       av_frame_->linesize[kYPlaneIndex], av_frame_->data[kUPlaneIndex],
       av_frame_->linesize[kUPlaneIndex], av_frame_->data[kVPlaneIndex],
-      av_frame_->linesize[kVPlaneIndex], rtc::KeepRefUntilDone(i420_buffer));
+      av_frame_->linesize[kVPlaneIndex],
+      // To keep reference alive.
+      [frame_buffer] {});
 
   if (preferred_output_format_ == VideoFrameBuffer::Type::kNV12) {
     const I420BufferInterface* cropped_i420 = cropped_buffer->GetI420();

modules/video_coding/codecs/multiplex/multiplex_decoder_adapter.cc

@@ -17,7 +17,6 @@
 #include "common_video/libyuv/include/webrtc_libyuv.h"
 #include "modules/video_coding/codecs/multiplex/include/augmented_video_frame_buffer.h"
 #include "modules/video_coding/codecs/multiplex/multiplex_encoded_image_packer.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/logging.h"
 
 namespace webrtc {

modules/video_coding/codecs/multiplex/multiplex_encoder_adapter.cc

@@ -18,7 +18,6 @@
 #include "common_video/libyuv/include/webrtc_libyuv.h"
 #include "media/base/video_common.h"
 #include "modules/video_coding/codecs/multiplex/include/augmented_video_frame_buffer.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/logging.h"
 
 namespace webrtc {
@@ -204,16 +203,18 @@ int MultiplexEncoderAdapter::Encode(
     return rv;
 
   // Encode AXX
-  const I420ABufferInterface* yuva_buffer =
+  rtc::scoped_refptr<VideoFrameBuffer> frame_buffer =
       supports_augmented_data_
-          ? augmented_video_frame_buffer->GetVideoFrameBuffer()->GetI420A()
+          ? augmented_video_frame_buffer->GetVideoFrameBuffer()
-          : input_image.video_frame_buffer()->GetI420A();
+          : input_image.video_frame_buffer();
+  const I420ABufferInterface* yuva_buffer = frame_buffer->GetI420A();
   rtc::scoped_refptr<I420BufferInterface> alpha_buffer =
       WrapI420Buffer(input_image.width(), input_image.height(),
                      yuva_buffer->DataA(), yuva_buffer->StrideA(),
                      multiplex_dummy_planes_.data(), yuva_buffer->StrideU(),
                      multiplex_dummy_planes_.data(), yuva_buffer->StrideV(),
-                     rtc::KeepRefUntilDone(input_image.video_frame_buffer()));
+                     // To keep reference alive.
+                     [frame_buffer] {});
   VideoFrame alpha_image = VideoFrame::Builder()
                                .set_video_frame_buffer(alpha_buffer)
                                .set_timestamp_rtp(input_image.timestamp())

modules/video_coding/codecs/multiplex/test/multiplex_adapter_unittest.cc

@@ -38,7 +38,6 @@
 #include "modules/video_coding/codecs/vp9/include/vp9.h"
 #include "modules/video_coding/include/video_codec_interface.h"
 #include "modules/video_coding/include/video_error_codes.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/ref_counted_object.h"
 #include "test/gmock.h"
 #include "test/gtest.h"
@@ -112,7 +111,9 @@ class TestMultiplexAdapter : public VideoCodecUnitTest,
         yuv_buffer->width(), yuv_buffer->height(), yuv_buffer->DataY(),
         yuv_buffer->StrideY(), yuv_buffer->DataU(), yuv_buffer->StrideU(),
         yuv_buffer->DataV(), yuv_buffer->StrideV(), yuv_buffer->DataY(),
-        yuv_buffer->StrideY(), rtc::KeepRefUntilDone(yuv_buffer));
+        yuv_buffer->StrideY(),
+        // To keep reference alive.
+        [yuv_buffer] {});
     return std::make_unique<VideoFrame>(VideoFrame::Builder()
                                             .set_video_frame_buffer(yuva_buffer)
                                             .set_timestamp_rtp(123)
@@ -168,8 +169,7 @@ class TestMultiplexAdapter : public VideoCodecUnitTest,
     rtc::scoped_refptr<I420BufferInterface> axx_buffer = WrapI420Buffer(
         yuva_buffer->width(), yuva_buffer->height(), yuva_buffer->DataA(),
         yuva_buffer->StrideA(), yuva_buffer->DataU(), yuva_buffer->StrideU(),
-        yuva_buffer->DataV(), yuva_buffer->StrideV(),
+        yuva_buffer->DataV(), yuva_buffer->StrideV(), [video_frame_buffer] {});
-        rtc::KeepRefUntilDone(video_frame_buffer));
     return std::make_unique<VideoFrame>(VideoFrame::Builder()
                                             .set_video_frame_buffer(axx_buffer)
                                             .set_timestamp_rtp(123)

modules/video_coding/codecs/vp9/libvpx_vp9_decoder.cc

@@ -22,7 +22,6 @@
 #include "common_video/include/video_frame_buffer.h"
 #include "modules/video_coding/utility/vp9_uncompressed_header_parser.h"
 #include "rtc_base/checks.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/logging.h"
 #include "third_party/libyuv/include/libyuv/convert.h"
 #include "vpx/vp8dx.h"
@@ -277,7 +276,7 @@ int LibvpxVp9Decoder::ReturnFrame(
   // This buffer contains all of |img|'s image data, a reference counted
   // Vp9FrameBuffer. (libvpx is done with the buffers after a few
   // vpx_codec_decode calls or vpx_codec_destroy).
-  Vp9FrameBufferPool::Vp9FrameBuffer* img_buffer =
+  rtc::scoped_refptr<Vp9FrameBufferPool::Vp9FrameBuffer> img_buffer =
       static_cast<Vp9FrameBufferPool::Vp9FrameBuffer*>(img->fb_priv);
 
   // The buffer can be used directly by the VideoFrame (without copy) by
@@ -312,7 +311,7 @@ int LibvpxVp9Decoder::ReturnFrame(
               // WrappedI420Buffer's mechanism for allowing the release of its
               // frame buffer is through a callback function. This is where we
               // should release |img_buffer|.
-              rtc::KeepRefUntilDone(img_buffer));
+              [img_buffer] {});
         }
       } else if (img->fmt == VPX_IMG_FMT_I444) {
         img_wrapped_buffer = WrapI444Buffer(
@@ -323,7 +322,7 @@ int LibvpxVp9Decoder::ReturnFrame(
             // WrappedI444Buffer's mechanism for allowing the release of its
             // frame buffer is through a callback function. This is where we
             // should release |img_buffer|.
-            rtc::KeepRefUntilDone(img_buffer));
+            [img_buffer] {});
       } else {
         RTC_LOG(LS_ERROR)
             << "Unsupported pixel format produced by the decoder: "
@@ -339,7 +338,7 @@ int LibvpxVp9Decoder::ReturnFrame(
           reinterpret_cast<const uint16_t*>(img->planes[VPX_PLANE_U]),
           img->stride[VPX_PLANE_U] / 2,
           reinterpret_cast<const uint16_t*>(img->planes[VPX_PLANE_V]),
-          img->stride[VPX_PLANE_V] / 2, rtc::KeepRefUntilDone(img_buffer));
+          img->stride[VPX_PLANE_V] / 2, [img_buffer] {});
       break;
     default:
       RTC_LOG(LS_ERROR) << "Unsupported bit depth produced by the decoder: "

p2p/stunprober/stun_prober.h

@@ -18,7 +18,6 @@
 #include "api/sequence_checker.h"
 #include "rtc_base/async_invoker.h"
 #include "rtc_base/byte_buffer.h"
-#include "rtc_base/callback.h"
 #include "rtc_base/constructor_magic.h"
 #include "rtc_base/ip_address.h"
 #include "rtc_base/network.h"
@@ -40,7 +39,7 @@ class StunProber;
 
 static const int kMaxUdpBufferSize = 1200;
 
-typedef rtc::Callback2<void, StunProber*, int> AsyncCallback;
+typedef std::function<void(StunProber*, int)> AsyncCallback;
 
 enum NatType {
   NATTYPE_INVALID,

pc/video_rtp_track_source.h

@@ -20,7 +20,6 @@
 #include "api/video/video_source_interface.h"
 #include "media/base/video_broadcaster.h"
 #include "pc/video_track_source.h"
-#include "rtc_base/callback.h"
 #include "rtc_base/constructor_magic.h"
 #include "rtc_base/synchronization/mutex.h"
 #include "rtc_base/system/no_unique_address.h"

rtc_base/BUILD.gn

@@ -972,7 +972,6 @@ rtc_library("rtc_base") {
     "helpers.h",
     "http_common.cc",
     "http_common.h",
-    "keep_ref_until_done.h",
     "mdns_responder_interface.h",
     "message_digest.cc",
     "message_digest.h",
@@ -1043,7 +1042,6 @@ rtc_library("rtc_base") {
     include_dirs = [ "../../boringssl/src/include" ]
   } else {
     sources += [
-      "callback.h",
       "log_sinks.cc",
       "log_sinks.h",
       "rolling_accumulator.h",
@@ -1484,7 +1482,6 @@ if (rtc_include_tests) {
       defines = []
 
       sources = [
-        "callback_unittest.cc",
         "crc32_unittest.cc",
         "data_rate_limiter_unittest.cc",
         "fake_clock_unittest.cc",

rtc_base/callback.h

@@ -1,250 +0,0 @@
-// This file was GENERATED by command:
-//     pump.py callback.h.pump
-// DO NOT EDIT BY HAND!!!
-
-/*
- *  Copyright 2012 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-// To generate callback.h from callback.h.pump, execute:
-// ../third_party/googletest/src/googletest/scripts/pump.py callback.h.pump
-
-// Callbacks are callable object containers. They can hold a function pointer
-// or a function object and behave like a value type. Internally, data is
-// reference-counted, making copies and pass-by-value inexpensive.
-//
-// Callbacks are typed using template arguments.  The format is:
-//   CallbackN<ReturnType, ParamType1, ..., ParamTypeN>
-// where N is the number of arguments supplied to the callable object.
-// Callbacks are invoked using operator(), just like a function or a function
-// object. Default-constructed callbacks are "empty," and executing an empty
-// callback does nothing. A callback can be made empty by assigning it from
-// a default-constructed callback.
-//
-// Callbacks are similar in purpose to std::function (which isn't available on
-// all platforms we support) and a lightweight alternative to sigslots. Since
-// they effectively hide the type of the object they call, they're useful in
-// breaking dependencies between objects that need to interact with one another.
-// Notably, they can hold the results of Bind(), std::bind*, etc, without
-// needing
-// to know the resulting object type of those calls.
-//
-// Sigslots, on the other hand, provide a fuller feature set, such as multiple
-// subscriptions to a signal, optional thread-safety, and lifetime tracking of
-// slots. When these features are needed, choose sigslots.
-//
-// Example:
-//   int sqr(int x) { return x * x; }
-//   struct AddK {
-//     int k;
-//     int operator()(int x) const { return x + k; }
-//   } add_k = {5};
-//
-//   Callback1<int, int> my_callback;
-//   cout << my_callback.empty() << endl;  // true
-//
-//   my_callback = Callback1<int, int>(&sqr);
-//   cout << my_callback.empty() << endl;  // false
-//   cout << my_callback(3) << endl;  // 9
-//
-//   my_callback = Callback1<int, int>(add_k);
-//   cout << my_callback(10) << endl;  // 15
-//
-//   my_callback = Callback1<int, int>();
-//   cout << my_callback.empty() << endl;  // true
-
-#ifndef RTC_BASE_CALLBACK_H_
-#define RTC_BASE_CALLBACK_H_
-
-#include "api/scoped_refptr.h"
-#include "rtc_base/ref_count.h"
-#include "rtc_base/ref_counted_object.h"
-
-namespace rtc {
-
-template <class R>
-class Callback0 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback0() {}
-  template <class T>
-  Callback0(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()() {
-    if (empty())
-      return R();
-    return helper_->Run();
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run() = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run() { return functor_(); }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-template <class R, class P1>
-class Callback1 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback1() {}
-  template <class T>
-  Callback1(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()(P1 p1) {
-    if (empty())
-      return R();
-    return helper_->Run(p1);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run(P1 p1) = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run(P1 p1) { return functor_(p1); }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-template <class R, class P1, class P2>
-class Callback2 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback2() {}
-  template <class T>
-  Callback2(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()(P1 p1, P2 p2) {
-    if (empty())
-      return R();
-    return helper_->Run(p1, p2);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run(P1 p1, P2 p2) = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run(P1 p1, P2 p2) { return functor_(p1, p2); }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-template <class R, class P1, class P2, class P3>
-class Callback3 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback3() {}
-  template <class T>
-  Callback3(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()(P1 p1, P2 p2, P3 p3) {
-    if (empty())
-      return R();
-    return helper_->Run(p1, p2, p3);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run(P1 p1, P2 p2, P3 p3) = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run(P1 p1, P2 p2, P3 p3) { return functor_(p1, p2, p3); }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-template <class R, class P1, class P2, class P3, class P4>
-class Callback4 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback4() {}
-  template <class T>
-  Callback4(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()(P1 p1, P2 p2, P3 p3, P4 p4) {
-    if (empty())
-      return R();
-    return helper_->Run(p1, p2, p3, p4);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run(P1 p1, P2 p2, P3 p3, P4 p4) = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run(P1 p1, P2 p2, P3 p3, P4 p4) {
-      return functor_(p1, p2, p3, p4);
-    }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-template <class R, class P1, class P2, class P3, class P4, class P5>
-class Callback5 {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback5() {}
-  template <class T>
-  Callback5(const T& functor)
-      : helper_(new RefCountedObject<HelperImpl<T> >(functor)) {}
-  R operator()(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5) {
-    if (empty())
-      return R();
-    return helper_->Run(p1, p2, p3, p4, p5);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5) = 0;
-  };
-  template <class T>
-  struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5) {
-      return functor_(p1, p2, p3, p4, p5);
-    }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-}  // namespace rtc
-
-#endif  // RTC_BASE_CALLBACK_H_

rtc_base/callback.h.pump

@@ -1,104 +0,0 @@
-/*
- *  Copyright 2012 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-// To generate callback.h from callback.h.pump, execute:
-// ../third_party/googletest/src/googletest/scripts/pump.py callback.h.pump
-
-// Callbacks are callable object containers. They can hold a function pointer
-// or a function object and behave like a value type. Internally, data is
-// reference-counted, making copies and pass-by-value inexpensive.
-//
-// Callbacks are typed using template arguments.  The format is:
-//   CallbackN<ReturnType, ParamType1, ..., ParamTypeN>
-// where N is the number of arguments supplied to the callable object.
-// Callbacks are invoked using operator(), just like a function or a function
-// object. Default-constructed callbacks are "empty," and executing an empty
-// callback does nothing. A callback can be made empty by assigning it from
-// a default-constructed callback.
-//
-// Callbacks are similar in purpose to std::function (which isn't available on
-// all platforms we support) and a lightweight alternative to sigslots. Since
-// they effectively hide the type of the object they call, they're useful in
-// breaking dependencies between objects that need to interact with one another.
-// Notably, they can hold the results of Bind(), std::bind*, etc, without needing
-// to know the resulting object type of those calls.
-//
-// Sigslots, on the other hand, provide a fuller feature set, such as multiple
-// subscriptions to a signal, optional thread-safety, and lifetime tracking of
-// slots. When these features are needed, choose sigslots.
-//
-// Example:
-//   int sqr(int x) { return x * x; }
-//   struct AddK {
-//     int k;
-//     int operator()(int x) const { return x + k; }
-//   } add_k = {5};
-//
-//   Callback1<int, int> my_callback;
-//   cout << my_callback.empty() << endl;  // true
-//
-//   my_callback = Callback1<int, int>(&sqr);
-//   cout << my_callback.empty() << endl;  // false
-//   cout << my_callback(3) << endl;  // 9
-//
-//   my_callback = Callback1<int, int>(add_k);
-//   cout << my_callback(10) << endl;  // 15
-//
-//   my_callback = Callback1<int, int>();
-//   cout << my_callback.empty() << endl;  // true
-
-#ifndef RTC_BASE_CALLBACK_H_
-#define RTC_BASE_CALLBACK_H_
-
-#include "rtc_base/ref_count.h"
-#include "rtc_base/ref_counted_object.h"
-#include "api/scoped_refptr.h"
-
-namespace rtc {
-
-$var n = 5
-$range i 0..n
-$for i [[
-$range j 1..i
-
-template <class R$for j [[,
-          class P$j]]>
-class Callback$i {
- public:
-  // Default copy operations are appropriate for this class.
-  Callback$i() {}
-  template <class T> Callback$i(const T& functor)
-      : helper_(new RefCountedObject< HelperImpl<T> >(functor)) {}
-  R operator()($for j , [[P$j p$j]]) {
-    if (empty())
-      return R();
-    return helper_->Run($for j , [[p$j]]);
-  }
-  bool empty() const { return !helper_; }
-
- private:
-  struct Helper : RefCountInterface {
-    virtual ~Helper() {}
-    virtual R Run($for j , [[P$j p$j]]) = 0;
-  };
-  template <class T> struct HelperImpl : Helper {
-    explicit HelperImpl(const T& functor) : functor_(functor) {}
-    virtual R Run($for j , [[P$j p$j]]) {
-      return functor_($for j , [[p$j]]);
-    }
-    T functor_;
-  };
-  scoped_refptr<Helper> helper_;
-};
-
-]]
-}  // namespace rtc
-
-#endif  // RTC_BASE_CALLBACK_H_

rtc_base/callback_unittest.cc

@@ -1,128 +0,0 @@
-/*
- *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "rtc_base/callback.h"
-
-#include "rtc_base/keep_ref_until_done.h"
-#include "rtc_base/ref_count.h"
-#include "test/gtest.h"
-
-namespace rtc {
-
-namespace {
-
-void f() {}
-int g() {
-  return 42;
-}
-int h(int x) {
-  return x * x;
-}
-void i(int& x) {
-  x *= x;
-}  // NOLINT: Testing refs
-
-class RefCountedBindTester : public RefCountInterface {
- public:
-  RefCountedBindTester() : count_(0) {}
-  void AddRef() const override { ++count_; }
-  RefCountReleaseStatus Release() const override {
-    --count_;
-    return count_ == 0 ? RefCountReleaseStatus::kDroppedLastRef
-                       : RefCountReleaseStatus::kOtherRefsRemained;
-  }
-  int RefCount() const { return count_; }
-
- private:
-  mutable int count_;
-};
-
-}  // namespace
-
-TEST(CallbackTest, VoidReturn) {
-  Callback0<void> cb;
-  EXPECT_TRUE(cb.empty());
-  cb();  // Executing an empty callback should not crash.
-  cb = Callback0<void>(&f);
-  EXPECT_FALSE(cb.empty());
-  cb();
-}
-
-TEST(CallbackTest, IntReturn) {
-  Callback0<int> cb;
-  EXPECT_TRUE(cb.empty());
-  cb = Callback0<int>(&g);
-  EXPECT_FALSE(cb.empty());
-  EXPECT_EQ(42, cb());
-  EXPECT_EQ(42, cb());
-}
-
-TEST(CallbackTest, OneParam) {
-  Callback1<int, int> cb1(&h);
-  EXPECT_FALSE(cb1.empty());
-  EXPECT_EQ(9, cb1(-3));
-  EXPECT_EQ(100, cb1(10));
-
-  // Try clearing a callback.
-  cb1 = Callback1<int, int>();
-  EXPECT_TRUE(cb1.empty());
-
-  // Try a callback with a ref parameter.
-  Callback1<void, int&> cb2(&i);
-  int x = 3;
-  cb2(x);
-  EXPECT_EQ(9, x);
-  cb2(x);
-  EXPECT_EQ(81, x);
-}
-
-TEST(KeepRefUntilDoneTest, simple) {
-  RefCountedBindTester t;
-  EXPECT_EQ(0, t.RefCount());
-  {
-    Callback0<void> cb = KeepRefUntilDone(&t);
-    EXPECT_EQ(1, t.RefCount());
-    cb();
-    EXPECT_EQ(1, t.RefCount());
-    cb();
-    EXPECT_EQ(1, t.RefCount());
-  }
-  EXPECT_EQ(0, t.RefCount());
-}
-
-TEST(KeepRefUntilDoneTest, copy) {
-  RefCountedBindTester t;
-  EXPECT_EQ(0, t.RefCount());
-  Callback0<void> cb2;
-  {
-    Callback0<void> cb = KeepRefUntilDone(&t);
-    EXPECT_EQ(1, t.RefCount());
-    cb2 = cb;
-  }
-  EXPECT_EQ(1, t.RefCount());
-  cb2 = Callback0<void>();
-  EXPECT_EQ(0, t.RefCount());
-}
-
-TEST(KeepRefUntilDoneTest, scopedref) {
-  RefCountedBindTester t;
-  EXPECT_EQ(0, t.RefCount());
-  {
-    scoped_refptr<RefCountedBindTester> t_scoped_ref(&t);
-    Callback0<void> cb = KeepRefUntilDone(t_scoped_ref);
-    t_scoped_ref = nullptr;
-    EXPECT_EQ(1, t.RefCount());
-    cb();
-    EXPECT_EQ(1, t.RefCount());
-  }
-  EXPECT_EQ(0, t.RefCount());
-}
-
-}  // namespace rtc

rtc_base/keep_ref_until_done.h

@@ -1,36 +0,0 @@
-/*
- *  Copyright 2015 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#ifndef RTC_BASE_KEEP_REF_UNTIL_DONE_H_
-#define RTC_BASE_KEEP_REF_UNTIL_DONE_H_
-
-#include "api/scoped_refptr.h"
-#include "rtc_base/callback.h"
-
-namespace rtc {
-
-// KeepRefUntilDone keeps a reference to |object| until the returned
-// callback goes out of scope. If the returned callback is copied, the
-// reference will be released when the last callback goes out of scope.
-template <class ObjectT>
-static inline Callback0<void> KeepRefUntilDone(ObjectT* object) {
-  scoped_refptr<ObjectT> p(object);
-  return [p] {};
-}
-
-template <class ObjectT>
-static inline Callback0<void> KeepRefUntilDone(
-    const scoped_refptr<ObjectT>& object) {
-  return [object] {};
-}
-
-}  // namespace rtc
-
-#endif  // RTC_BASE_KEEP_REF_UNTIL_DONE_H_

sdk/android/native_api/video/video_source.cc

@@ -10,6 +10,7 @@
 
 #include "sdk/android/native_api/video/video_source.h"
 
+#include "rtc_base/ref_counted_object.h"
 #include "sdk/android/src/jni/android_video_track_source.h"
 #include "sdk/android/src/jni/native_capturer_observer.h"
 

sdk/android/src/jni/pc/video.cc

@@ -16,6 +16,7 @@
 #include "api/video_codecs/video_decoder_factory.h"
 #include "api/video_codecs/video_encoder_factory.h"
 #include "rtc_base/logging.h"
+#include "rtc_base/ref_counted_object.h"
 #include "sdk/android/native_api/jni/java_types.h"
 #include "sdk/android/src/jni/android_video_track_source.h"
 #include "sdk/android/src/jni/video_decoder_factory_wrapper.h"

sdk/android/src/jni/video_frame.cc

@@ -15,8 +15,8 @@
 #include "api/scoped_refptr.h"
 #include "common_video/include/video_frame_buffer.h"
 #include "rtc_base/checks.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "rtc_base/logging.h"
+#include "rtc_base/ref_counted_object.h"
 #include "rtc_base/time_utils.h"
 #include "sdk/android/generated_video_jni/VideoFrame_jni.h"
 #include "sdk/android/src/jni/jni_helpers.h"

sdk/android/src/jni/video_frame.h

@@ -16,7 +16,6 @@
 #include "api/video/video_frame.h"
 #include "api/video/video_frame_buffer.h"
 #include "api/video/video_rotation.h"
-#include "rtc_base/callback.h"
 #include "sdk/android/src/jni/jni_helpers.h"
 
 namespace webrtc {

test/frame_generator.cc

@@ -21,7 +21,6 @@
 #include "common_video/include/video_frame_buffer.h"
 #include "common_video/libyuv/include/webrtc_libyuv.h"
 #include "rtc_base/checks.h"
-#include "rtc_base/keep_ref_until_done.h"
 #include "test/frame_utils.h"
 
 namespace webrtc {
@@ -368,7 +367,8 @@ void ScrollingImageFrameGenerator::CropSourceToScrolledImage(
                      &i420_buffer->DataY()[offset_y], i420_buffer->StrideY(),
                      &i420_buffer->DataU()[offset_u], i420_buffer->StrideU(),
                      &i420_buffer->DataV()[offset_v], i420_buffer->StrideV(),
-                     KeepRefUntilDone(i420_buffer)),
+                     // To keep reference alive.
+                     [i420_buffer] {}),
       update_rect);
 }