Add renderer-agnostic delegate protocol.

The MTL renderer should also have a way to notify it's delegate
that it's content size changed.

The plan is to introduce this new protocol, move existing clients over
to implementing it in favour of RTCEAGLVideoViewDelegate, and then finally
removing the old protocol.

Bug: b/73147161
Change-Id: I908d7b2667e44e02a58066d701a48efec0e98d14
Reviewed-on: https://webrtc-review.googlesource.com/70243
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Anders Carlsson <andersc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22944}

sdk/BUILD.gn

@@ -700,7 +700,7 @@ if (is_ios || is_mac) {
           ]
 
           if (rtc_use_metal_rendering) {
-            sources += [ "objc/Framework/UnitTests/RTCMTLVideoView_xctest.mm" ]
+            sources += [ "objc/Framework/UnitTests/RTCMTLVideoView_xctest.m" ]
             deps += [ ":metal_objc" ]
           }
 

sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m

@@ -27,6 +27,7 @@
   id<RTCMTLRenderer> _renderer;
 }
 
+@synthesize delegate = _delegate;
 @synthesize renderer = _renderer;
 @synthesize metalView = _metalView;
 @synthesize videoFrame = _videoFrame;
@@ -105,6 +106,9 @@
 
 - (void)setSize:(CGSize)size {
   _metalView.drawableSize = size;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    [self.delegate videoView:self didChangeVideoSize:size];
+  });
   [_metalView draw];
 }
 

sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m

@@ -37,6 +37,7 @@
   int64_t _lastFrameTimeNs;
 }
 
+@synthesize delegate = _delegate;
 @synthesize rendererI420 = _rendererI420;
 @synthesize rendererNV12 = _rendererNV12;
 @synthesize metalView = _metalView;
@@ -144,6 +145,9 @@
 
 - (void)setSize:(CGSize)size {
   self.metalView.drawableSize = size;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    [self.delegate videoView:self didChangeVideoSize:size];
+  });
 }
 
 - (void)renderFrame:(nullable RTCVideoFrame *)frame {

sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h

@@ -18,11 +18,9 @@
 NS_ASSUME_NONNULL_BEGIN
 
 @class RTCEAGLVideoView;
+
 RTC_EXPORT
-@protocol RTCEAGLVideoViewDelegate
-
-- (void)videoView:(RTCEAGLVideoView *)videoView didChangeVideoSize:(CGSize)size;
-
+@protocol RTCEAGLVideoViewDelegate<RTCVideoViewDelegate>
 @end
 
 /**
@@ -32,7 +30,7 @@ RTC_EXPORT
 RTC_EXPORT
 @interface RTCEAGLVideoView : UIView <RTCVideoRenderer>
 
-@property(nonatomic, weak) id<RTCEAGLVideoViewDelegate> delegate;
+@property(nonatomic, weak) id<RTCVideoViewDelegate> delegate;
 
 - (instancetype)initWithFrame:(CGRect)frame
                        shader:(id<RTCVideoViewShading>)shader NS_DESIGNATED_INITIALIZER;

sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h

@@ -13,5 +13,8 @@
 
 NS_AVAILABLE_MAC(10.11)
 @interface RTCMTLNSVideoView : NSView<RTCVideoRenderer>
+
+@property(nonatomic, weak) id<RTCVideoViewDelegate> delegate;
+
 + (BOOL)isMetalAvailable;
 @end

sdk/objc/Framework/Headers/WebRTC/RTCMTLVideoView.h

@@ -32,6 +32,7 @@ NS_CLASS_AVAILABLE_IOS(9)
 
 RTC_EXPORT
 @interface RTCMTLVideoView : UIView <RTCVideoRenderer>
-
+@property(nonatomic, weak) id<RTCVideoViewDelegate> delegate;
 @end
+
 NS_ASSUME_NONNULL_END

sdk/objc/Framework/Headers/WebRTC/RTCNSGLVideoView.h

@@ -20,15 +20,13 @@
 NS_ASSUME_NONNULL_BEGIN
 
 @class RTCNSGLVideoView;
-@protocol RTCNSGLVideoViewDelegate
-
-- (void)videoView:(RTCNSGLVideoView *)videoView didChangeVideoSize:(CGSize)size;
 
+@protocol RTCNSGLVideoViewDelegate<RTCVideoViewDelegate>
 @end
 
 @interface RTCNSGLVideoView : NSOpenGLView <RTCVideoRenderer>
 
-@property(nonatomic, weak) id<RTCNSGLVideoViewDelegate> delegate;
+@property(nonatomic, weak) id<RTCVideoViewDelegate> delegate;
 
 - (instancetype)initWithFrame:(NSRect)frameRect
                   pixelFormat:(NSOpenGLPixelFormat *)format

sdk/objc/Framework/Headers/WebRTC/RTCVideoRenderer.h

@@ -30,4 +30,11 @@ RTC_EXPORT
 
 @end
 
+RTC_EXPORT
+@protocol RTCVideoViewDelegate
+
+- (void)videoView:(id<RTCVideoRenderer>)videoView didChangeVideoSize:(CGSize)size;
+
+@end
+
 NS_ASSUME_NONNULL_END

sdk/objc/Framework/UnitTests/RTCMTLVideoView_xctest.m

@@ -62,12 +62,8 @@
   id frameMock = OCMClassMock([RTCVideoFrame class]);
   if (hasCVPixelBuffer) {
     CVPixelBufferRef pixelBufferRef;
-    CVPixelBufferCreate(kCFAllocatorDefault,
-                        200,
-                        200,
-                        kCVPixelFormatType_420YpCbCr8Planar,
-                        nullptr,
-                        &pixelBufferRef);
+    CVPixelBufferCreate(
+        kCFAllocatorDefault, 200, 200, kCVPixelFormatType_420YpCbCr8Planar, nil, &pixelBufferRef);
     OCMStub([frameMock buffer])
         .andReturn([[RTCCVPixelBuffer alloc] initWithPixelBuffer:pixelBufferRef]);
   } else {
@@ -247,4 +243,19 @@
   [self.rendererNV12Mock verify];
 }
 
+- (void)testReportsSizeChangesToDelegate {
+  OCMStub([self.classMock isMetalAvailable]).andReturn(YES);
+
+  id delegateMock = OCMProtocolMock(@protocol(RTCVideoViewDelegate));
+  CGSize size = CGSizeMake(640, 480);
+  OCMExpect([delegateMock videoView:[OCMArg any] didChangeVideoSize:size]);
+
+  RTCMTLVideoView *realView = [[RTCMTLVideoView alloc] init];
+  realView.delegate = delegateMock;
+  [realView setSize:size];
+
+  // Delegate method is invoked with a dispatch_async.
+  OCMVerifyAllWithDelay(delegateMock, 1);
+}
+
 @end