Delete VideoRendererInterface.

Use in chromium was deleted a few days ago.

BUG=webrtc:5426
R=magjed@webrtc.org, pbos@webrtc.org, perkj@webrtc.org, pthatcher@webrtc.org, tkchin@webrtc.org

Review URL: https://codereview.webrtc.org/1817473002 .

Cr-Commit-Position: refs/heads/master@{#12099}
diff --git a/webrtc/api/objc/RTCVideoRendererAdapter+Private.h b/webrtc/api/objc/RTCVideoRendererAdapter+Private.h
index c181b9b..f0e0c6c 100644
--- a/webrtc/api/objc/RTCVideoRendererAdapter+Private.h
+++ b/webrtc/api/objc/RTCVideoRendererAdapter+Private.h
@@ -26,12 +26,12 @@
 @property(nonatomic, readonly) id<RTCVideoRenderer> videoRenderer;
 
 /**
- * The native VideoRendererInterface surface exposed by this adapter. Calls made
+ * The native VideoSinkInterface surface exposed by this adapter. Calls made
  * to this interface will be adapted and passed to the RTCVideoRenderer supplied
  * during construction. This pointer is unsafe and owned by this class.
  */
 @property(nonatomic, readonly)
-    webrtc::VideoRendererInterface *nativeVideoRenderer;
+    rtc::VideoSinkInterface<cricket::VideoFrame> *nativeVideoRenderer;
 
 /** Initialize an RTCVideoRendererAdapter with an RTCVideoRenderer. */
 - (instancetype)initWithNativeRenderer:(id<RTCVideoRenderer>)videoRenderer