Clean up RTCVideoFrame

RTCVideoFrame is an ObjectiveC version of webrtc::VideoFrame, but it
currently contains some extra logic beyond that. We want RTCVideoFrame
to be as simple as possible, i.e. just a container with no extra state,
so we can use it as input to RTCVideoSource without complicating the
interface for consumers.

BUG=webrtc:7177
NOTRY=True

Review-Url: https://codereview.webrtc.org/2695203004
Cr-Commit-Position: refs/heads/master@{#16740}
diff --git a/webrtc/sdk/objc/Framework/Classes/RTCShader.mm b/webrtc/sdk/objc/Framework/Classes/RTCShader.mm
index 26dc64f..155a016 100644
--- a/webrtc/sdk/objc/Framework/Classes/RTCShader.mm
+++ b/webrtc/sdk/objc/Framework/Classes/RTCShader.mm
@@ -138,7 +138,7 @@
 }
 
 // Set vertex data to the currently bound vertex buffer.
-void RTCSetVertexData(webrtc::VideoRotation rotation) {
+void RTCSetVertexData(RTCVideoRotation rotation) {
   // When modelview and projection matrices are identity (default) the world is
   // contained in the square around origin with unit size 2. Drawing to these
   // coordinates is equivalent to drawing to the entire screen. The texture is
@@ -156,16 +156,16 @@
   // Rotate the UV coordinates.
   int rotation_offset;
   switch (rotation) {
-    case webrtc::kVideoRotation_0:
+    case RTCVideoRotation_0:
       rotation_offset = 0;
       break;
-    case webrtc::kVideoRotation_90:
+    case RTCVideoRotation_90:
       rotation_offset = 1;
       break;
-    case webrtc::kVideoRotation_180:
+    case RTCVideoRotation_180:
       rotation_offset = 2;
       break;
-    case webrtc::kVideoRotation_270:
+    case RTCVideoRotation_270:
       rotation_offset = 3;
       break;
   }