Makes copying layers clone external textures.

content/common/gpu/client/gl_helper.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
 #define CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_
 
 #include "base/atomicops.h"
 #include "base/basictypes.h"
 #include "base/callback.h"
@@ skipping 21 matching lines @@
   // scales it to |dst_size|, and writes it into |out|.
   // |src_size| is the size of |src_texture|. |callback| is invoked with the
   // copy result when the copy operation has completed.
   void CopyTextureTo(WebKit::WebGLId src_texture,
                      const gfx::Size& src_size,
                      const gfx::Rect& src_subrect,
                      const gfx::Size& dst_size,
                      unsigned char* out,
                      const base::Callback<void(bool)>& callback);
 
+  // Creates a copy of the specified texture. |size| is the size of the texture.
+  WebKit::WebGLId CopyTexture(WebKit::WebGLId texture,
+                              const gfx::Size& size);
+
   // Returns the shader compiled from the source.
   WebKit::WebGLId CompileShaderFromSource(const WebKit::WGC3Dchar* source,
                                           WebKit::WGC3Denum type);
 
  private:
   class CopyTextureToImpl;
 
+  // Creates |copy_texture_to_impl_| if NULL.
+  void InitCopyTextToImpl();
+
   WebKit::WebGraphicsContext3D* context_;
   WebKit::WebGraphicsContext3D* context_for_thread_;
   scoped_ptr<CopyTextureToImpl> copy_texture_to_impl_;
 
   // The number of all GLHelper instances.
   static base::subtle::Atomic32 count_;
 
   DISALLOW_COPY_AND_ASSIGN(GLHelper);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_GL_HELPER_H_