Add support for multiple pixel formats in VideoFrameBuffer

webrtc/api/video/i420_buffer.h

Index: webrtc/api/video/i420_buffer.h
diff --git a/webrtc/api/video/i420_buffer.h b/webrtc/api/video/i420_buffer.h
index 388a3dd76903ad9e8f24a7d841f6220c2d994a21..4fcbb3c9e07d8d77e3e81b8d83f8b9ea14a70235 100644
--- a/webrtc/api/video/i420_buffer.h
+++ b/webrtc/api/video/i420_buffer.h
@@ -20,7 +20,7 @@
 namespace webrtc {
 
 // Plain I420 buffer in standard memory.
-class I420Buffer : public VideoFrameBuffer {
+class I420Buffer : public I420BufferInterface {
  public:
   static rtc::scoped_refptr<I420Buffer> Create(int width, int height);
   static rtc::scoped_refptr<I420Buffer> Create(int width,
@@ -66,9 +66,6 @@ class I420Buffer : public VideoFrameBuffer {
   int StrideU() const override;
   int StrideV() const override;
 
-  void* native_handle() const override;
-  rtc::scoped_refptr<VideoFrameBuffer> NativeToI420Buffer() override;
-
   uint8_t* MutableDataY();
   uint8_t* MutableDataU();
   uint8_t* MutableDataV();