Implement TextureImageTransportSurface using texture mailbox

content/common/gpu/client/gl_helper.h

Index: content/common/gpu/client/gl_helper.h
diff --git a/content/common/gpu/client/gl_helper.h b/content/common/gpu/client/gl_helper.h
index fd9f83a9cf047a49603cd9611d49d4e80105549a..222dd9c4ec3cd193ec5489c04f6ddcba4dc0460b 100644
--- a/content/common/gpu/client/gl_helper.h
+++ b/content/common/gpu/client/gl_helper.h
@@ -53,13 +53,15 @@ class GLHelper {
 
   // Creates a copy of the specified texture. |size| is the size of the texture.
   WebKit::WebGLId CopyTexture(WebKit::WebGLId texture,
-                              const gfx::Size& size);
+                              const gfx::Size& size,
+                              WebKit::WebGLId texture_out = 0);
 
   // Creates a scaled copy of the specified texture. |src_size| is the size of
   // the texture and |dst_size| is the size of the resulting copy.
   WebKit::WebGLId CopyAndScaleTexture(WebKit::WebGLId texture,
                                       const gfx::Size& src_size,
-                                      const gfx::Size& dst_size);
+                                      const gfx::Size& dst_size,
+                                      WebKit::WebGLId texture_out = 0);
 
   // Returns the shader compiled from the source.
   WebKit::WebGLId CompileShaderFromSource(const WebKit::WGC3Dchar* source,