iOS: Add interface for injecting custom shaders

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

Index: webrtc/sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h
diff --git a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h
index 5f8d73bc8d657991923aa0628246c5f68117cc6c..e8a3dcba3a57ad0f0a66b26d6956938f2581a836 100644
--- a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h
+++ b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h
@@ -13,6 +13,7 @@
 
 #import <WebRTC/RTCMacros.h>
 #import <WebRTC/RTCVideoRenderer.h>
+#import <WebRTC/RTCVideoViewShaderDelegate.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -26,13 +27,21 @@ RTC_EXPORT
 
 /**
  * RTCEAGLVideoView is an RTCVideoRenderer which renders video frames in its
- * bounds using OpenGLES 2.0.
+ * bounds using OpenGLES 2.0 or OpenGLES 3.0.
  */
 RTC_EXPORT
 @interface RTCEAGLVideoView : UIView <RTCVideoRenderer>
 
 @property(nonatomic, weak) id<RTCEAGLVideoViewDelegate> delegate;
 
+- (instancetype)initWithFrame:(CGRect)frame

[sakal, 2017/05/11 10:45:47]

Should we mark the default initializer as unavailable?

[magjed_webrtc, 2017/05/11 12:38:06]

The default initializers are still available. That's where we create the
DefaultShader and call these initializers.

+               shaderDelegate:(id<RTCVideoViewShaderDelegate>)shaderDelegate
+    NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)initWithCoder:(NSCoder *)aDecoder
+               shaderDelegate:(id<RTCVideoViewShaderDelegate>)shaderDelegate
+    NS_DESIGNATED_INITIALIZER;
+
 @end
 
 NS_ASSUME_NONNULL_END