Cleanup of webrtc::VideoFrame.

Delete EqualsFrame method, used only by tests. Delete one of the
CreateFrame methods. Drop return value for CreateEmptyFrame, CreateFrame
and CopyFrame.

BUG=webrtc:5426

Review URL: https://codereview.webrtc.org/1679323002

Cr-Commit-Position: refs/heads/master@{#11783}

webrtc/test/frame_utils.cc

@@ -0,0 +1,51 @@
+/*
+ *  Copyright (c) 2013 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 "webrtc/test/frame_utils.h"
+#include "webrtc/video_frame.h"
+
+namespace webrtc {
+namespace test {
+
+bool EqualPlane(const uint8_t* data1,
+                const uint8_t* data2,
+                int stride,
+                int width,
+                int height) {
+  for (int y = 0; y < height; ++y) {
+    if (memcmp(data1, data2, width) != 0)
+      return false;
+    data1 += stride;
+    data2 += stride;
+  }
+  return true;
+}
+bool FramesEqual(const webrtc::VideoFrame& f1, const webrtc::VideoFrame& f2) {
+  if (f1.width() != f2.width() || f1.height() != f2.height() ||
+      f1.stride(webrtc::kYPlane) != f2.stride(webrtc::kYPlane) ||
+      f1.stride(webrtc::kUPlane) != f2.stride(webrtc::kUPlane) ||
+      f1.stride(webrtc::kVPlane) != f2.stride(webrtc::kVPlane) ||
+      f1.timestamp() != f2.timestamp() ||
+      f1.ntp_time_ms() != f2.ntp_time_ms() ||
+      f1.render_time_ms() != f2.render_time_ms()) {
+    return false;
+  }
+  const int half_width = (f1.width() + 1) / 2;
+  const int half_height = (f1.height() + 1) / 2;
+  return EqualPlane(f1.buffer(webrtc::kYPlane), f2.buffer(webrtc::kYPlane),
+                    f1.stride(webrtc::kYPlane), f1.width(), f1.height()) &&
+         EqualPlane(f1.buffer(webrtc::kUPlane), f2.buffer(webrtc::kUPlane),
+                    f1.stride(webrtc::kUPlane), half_width, half_height) &&
+         EqualPlane(f1.buffer(webrtc::kVPlane), f2.buffer(webrtc::kVPlane),
+                    f1.stride(webrtc::kVPlane), half_width, half_height);
+}
+
+}  // namespace test
+}  // namespace webrtc