Add unit tests for RTCMTLVideoView.

webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h

Index: webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h
diff --git a/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h b/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h
index 0508e78db5c6338e67b73322d7e3c89be0cde282..4f7b25eefa7857af41b41729305b8e579259666a 100644
--- a/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h
+++ b/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.h
@@ -24,12 +24,6 @@
  * @param frame The frame to be rendered.
  */
 - (void)drawFrame:(RTCVideoFrame *)frame;
-@end
-
-/**
- * Implementation of RTCMTLRenderer protocol for rendering native nv12 video frames.
- */
-@interface RTCMTLNV12Renderer : NSObject <RTCMTLRenderer>
 
 /**
  * Sets the provided view as rendering destination if possible.
@@ -37,5 +31,13 @@
  * If not possible method returns NO and callers of the method are responisble for performing
  * cleanups.
  */
-- (BOOL)addRenderingDestination:(__kindof MTKView *)view;
+- (BOOL)addRenderingDestination:(__kindof UIView *)view;
+
+@end
+
+/**
+ * Implementation of RTCMTLRenderer protocol for rendering native nv12 video frames.
+ */
+@interface RTCMTLNV12Renderer : NSObject <RTCMTLRenderer>
+
 @end