[Reland 2] Pepper takes ownership of a mailbox before passing it to the texture layer.

gpu/command_buffer/service/gles2_cmd_decoder.h

Index: gpu/command_buffer/service/gles2_cmd_decoder.h
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.h b/gpu/command_buffer/service/gles2_cmd_decoder.h
index 0335df74c53f8929aacb871d7b56893acbf95fdf..adcb50d10bdb3b7cc0b021cf1fa3a2a8daba6ab5 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.h
@@ -162,7 +162,8 @@ class GPU_EXPORT GLES2Decoder : public base::SupportsWeakPtr<GLES2Decoder>,
   // The decoder should not be used until a new surface is set.
   virtual void ReleaseSurface() = 0;
 
-  virtual void ProduceFrontBuffer(const Mailbox& mailbox) = 0;
+  virtual void TakeFrontBuffer(const Mailbox& mailbox) = 0;
+  virtual void ReturnFrontBuffer(const Mailbox& mailbox, bool is_lost) = 0;
 
   // Resize an offscreen frame buffer.
   virtual bool ResizeOffscreenFrameBuffer(const gfx::Size& size) = 0;
@@ -204,6 +205,8 @@ class GPU_EXPORT GLES2Decoder : public base::SupportsWeakPtr<GLES2Decoder>,
   virtual void SetIgnoreCachedStateForTest(bool ignore) = 0;
   virtual void SetForceShaderNameHashingForTest(bool force) = 0;
   virtual uint32_t GetAndClearBackbufferClearBitsForTest();
+  virtual size_t GetSavedBackTextureCountForTest() = 0;
+  virtual size_t GetCreatedBackTextureCountForTest() = 0;
 
   // Gets the QueryManager for this context.
   virtual QueryManager* GetQueryManager() = 0;