Fix crash with pepper 3D on multiple windows in same renderer

content/renderer/ggl.cc

 // Copyright (c) 2010 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.
 
 #include "content/renderer/ggl.h"
 
 #include "base/lazy_instance.h"
 #include "base/ref_counted.h"
 #include "base/weak_ptr.h"
 #include "chrome/renderer/command_buffer_proxy.h"
@@ skipping 542 matching lines @@
   if (!context)
     return false;
 
   delete context;
   return true;
 #else
   return false;
 #endif
 }
 
+base::WeakPtr<Context> GetWeakContextReference(Context* context) {
+#if defined(ENABLE_GPU)
+  return context ? context->AsWeakPtr() : base::WeakPtr<Context>();
+#else
+  return base::WeakPtr<Context>();
+#endif
+}
+
 media::VideoDecodeEngine* CreateVideoDecodeEngine(Context* context) {
   return context->CreateVideoDecodeEngine();
 }
 
 media::VideoDecodeContext* CreateVideoDecodeContext(
     Context* context, MessageLoop* message_loop, bool hardware_decoder) {
   return context->CreateVideoDecodeContext(message_loop, hardware_decoder);
 }
 
 Error GetError(Context* context) {
@@ skipping 23 matching lines @@
 
   return context->gles2_implementation();
 }
 
 CommandBufferProxy* GetCommandBufferProxy(Context* context) {
   DCHECK(context);
   return context->command_buffer();
 }
 
 }  // namespace ggl