ReleaseOutputBuffer to surface back and front buffers where possible.

content/common/gpu/media/avda_codec_image.h

Index: content/common/gpu/media/avda_codec_image.h
diff --git a/content/common/gpu/media/avda_codec_image.h b/content/common/gpu/media/avda_codec_image.h
index 71baf25ce157fd73fe8aaed2dc3d4e19119a81f0..1914fd09c280952d4c1eb67e77d0b855c0630003 100644
--- a/content/common/gpu/media/avda_codec_image.h
+++ b/content/common/gpu/media/avda_codec_image.h
@@ -52,13 +52,23 @@ class AVDACodecImage : public gpu::gles2::GLStreamTextureImage {
   // Decoded buffer index that has the image for us to display.
   void SetMediaCodecBufferIndex(int buffer_index);
 
-  // Return the codec buffer that we will return to the codec, or
-  // <0 if there is no such buffer.
-  int GetMediaCodecBufferIndex() const;
-
   // Set the size of the current image.
   void SetSize(const gfx::Size& size);
 
+  enum class ReleaseMode { SKIP_RENDER, RENDER_ONLY, RENDER_AND_UPDATE };

[liberato (no reviews please), 2016/04/22 00:51:06]

i think these might be better named { DISCARD_CODEC_BUFFER,
RENDER_TO_BACK_BUFFER, RENDER_TO_FRONT_BUFFER}

RENDER_AND_UPDATE is used for the surfaceview case, but there's no notion of
updating.

[DaleCurtis, 2016/04/22 01:33:58]

I like it. Done.

+  void ReleaseOutputBuffer(ReleaseMode release_mode);
+
+  // Indicates if the codec buffer has been released to the back buffer.
+  bool is_rendered_to_back_buffer() const {
+    return codec_buffer_index_ == kUpdateOnly;
+  }
+
+  // Indicates if the codec buffer has been released to the front or back
+  // buffer.
+  bool is_rendered() const {
+    return codec_buffer_index_ <= kInvalidCodecBufferIndex;
+  }
+
   // Updates the MediaCodec for this image; clears |codec_buffer_index_|.
   void SetMediaCodec(media::MediaCodecBridge* codec);
 
@@ -67,9 +77,9 @@ class AVDACodecImage : public gpu::gles2::GLStreamTextureImage {
  protected:
   ~AVDACodecImage() override;
 
- private:
-  enum { kInvalidCodecBufferIndex = -1 };
+  enum { kInvalidCodecBufferIndex = -1, kUpdateOnly = -2 };
 
+ private:
   // Make sure that the surface texture's front buffer is current.  This will
   // save / restore the current context.  It will optionally restore the texture
   // bindings in the surface texture's context, based on |mode|.  This is