Allow the renderer process to map textures from one context into another.

content/renderer/gpu/webgraphicscontext3d_command_buffer_impl.cc

 // Copyright (c) 2011 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.
 
 #if defined(ENABLE_GPU)
 
 #include "content/renderer/gpu/webgraphicscontext3d_command_buffer_impl.h"
 
 #include <GLES2/gl2.h>
 #ifndef GL_GLEXT_PROTOTYPES
@@ skipping 315 matching lines @@
 }
 
 void WebGraphicsContext3DCommandBufferImpl::unmapTexSubImage2DCHROMIUM(
     const void* mem) {
   gl_->UnmapTexSubImage2DCHROMIUM(mem);
 }
 
 void WebGraphicsContext3DCommandBufferImpl::copyTextureToParentTextureCHROMIUM(
     WebGLId texture, WebGLId parentTexture) {
   TRACE_EVENT0("gpu", "WebGfxCtx3DCmdBfrImpl::copyTextureToCompositor");
-  gl_->CopyTextureToParentTextureCHROMIUM(texture, parentTexture);
+
   gl_->Flush();
+  context_->MapExternalResourceToParent(gpu::resource_type::kTexture,
+                                        texture,
+                                        parentTexture);
 }
 
 void WebGraphicsContext3DCommandBufferImpl::
     rateLimitOffscreenContextCHROMIUM() {
   gl_->RateLimitOffscreenContextCHROMIUM();
 }
 
 WebKit::WebString WebGraphicsContext3DCommandBufferImpl::
     getRequestableExtensionsCHROMIUM() {
   return WebKit::WebString::fromUTF8(
@@ skipping 671 matching lines @@
     context_lost_callback_->onContextLost();
   }
 
   RenderView* renderview =
       web_view_ ? RenderView::FromWebView(web_view_) : NULL;
   if (renderview)
     renderview->OnViewContextSwapBuffersAborted();
 }
 
 #endif  // defined(ENABLE_GPU)