iOS: Add interface for injecting custom shaders

webrtc/sdk/BUILD.gn

Index: webrtc/sdk/BUILD.gn
diff --git a/webrtc/sdk/BUILD.gn b/webrtc/sdk/BUILD.gn
index fa44c48fb3ebcc9df38048a1a981cb85a9ca54ea..701ea1eeb9e791a6f9a539f695758e6186e4f03b 100644
--- a/webrtc/sdk/BUILD.gn
+++ b/webrtc/sdk/BUILD.gn
@@ -125,7 +125,8 @@ if (is_ios || is_mac) {
       "objc/Framework/Classes/RTCDataChannel.mm",
       "objc/Framework/Classes/RTCDataChannelConfiguration+Private.h",
       "objc/Framework/Classes/RTCDataChannelConfiguration.mm",
-      "objc/Framework/Classes/RTCI420Shader.mm",
+      "objc/Framework/Classes/RTCDefaultShader.h",
+      "objc/Framework/Classes/RTCDefaultShader.mm",
       "objc/Framework/Classes/RTCI420TextureCache.h",
       "objc/Framework/Classes/RTCI420TextureCache.mm",
       "objc/Framework/Classes/RTCIceCandidate+Private.h",
@@ -161,7 +162,6 @@ if (is_ios || is_mac) {
       "objc/Framework/Classes/RTCRtpSender.mm",
       "objc/Framework/Classes/RTCSessionDescription+Private.h",
       "objc/Framework/Classes/RTCSessionDescription.mm",
-      "objc/Framework/Classes/RTCShader+Private.h",
       "objc/Framework/Classes/RTCShader.h",
       "objc/Framework/Classes/RTCShader.mm",
       "objc/Framework/Classes/RTCVideoCapturer.m",
@@ -209,6 +209,7 @@ if (is_ios || is_mac) {
       "objc/Framework/Headers/WebRTC/RTCVideoRenderer.h",
       "objc/Framework/Headers/WebRTC/RTCVideoSource.h",
       "objc/Framework/Headers/WebRTC/RTCVideoTrack.h",
+      "objc/Framework/Headers/WebRTC/RTCVideoViewShader.h",
     ]
 
     deps = [
@@ -228,7 +229,6 @@ if (is_ios || is_mac) {
         "objc/Framework/Classes/RTCEAGLVideoView.m",
         "objc/Framework/Classes/RTCNV12TextureCache.h",
         "objc/Framework/Classes/RTCNV12TextureCache.m",
-        "objc/Framework/Classes/RTCNativeNV12Shader.mm",
         "objc/Framework/Headers/WebRTC/RTCEAGLVideoView.h",
       ]
       libs = [