Upgrade PixelStorei to ES3/WebGL2.

gpu/command_buffer/service/context_state.h

Index: gpu/command_buffer/service/context_state.h
diff --git a/gpu/command_buffer/service/context_state.h b/gpu/command_buffer/service/context_state.h
index f9d4ff7b1929f1c2cce2a15757558e0375c4793f..71bb8a560645dd7a980bac14e710c16199db8669 100644
--- a/gpu/command_buffer/service/context_state.h
+++ b/gpu/command_buffer/service/context_state.h
@@ -266,6 +266,13 @@ struct GPU_EXPORT ContextState {
  private:
   void EnableDisable(GLenum pname, bool enable) const;
 
+  // If a buffer object is bound to PIXEL_PACK_BUFFER, set all pack parameters
+  // user values; otherwise, set them to 0.
+  void UpdatePackParameters() const;
+  // If a buffer object is bound to PIXEL_UNPACK_BUFFER, set all unpack
+  // parameters user values; otherwise, set them to 0.
+  void UpdateUnpackParameters() const;
+
   FeatureInfo* feature_info_;
   scoped_ptr<ErrorState> error_state_;
 };