Decouple cc::FakeWebGraphicsContext3D from blink::WGC3D

cc/test/test_context_provider.cc

 // Copyright 2013 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 "cc/test/test_context_provider.h"
 
 #include <set>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 75 matching lines @@
 }
 
 ContextProvider::Capabilities TestContextProvider::ContextCapabilities() {
   DCHECK(bound_);
   DCHECK(context_thread_checker_.CalledOnValidThread());
 
   return context3d_->test_capabilities();
 }
 
 blink::WebGraphicsContext3D* TestContextProvider::Context3d() {
-  DCHECK(bound_);
-  DCHECK(context_thread_checker_.CalledOnValidThread());
-
-  return context3d_.get();
+  return NULL;
 }
 
 gpu::gles2::GLES2Interface* TestContextProvider::ContextGL() {
   DCHECK(context3d_);
   DCHECK(bound_);
   DCHECK(context_thread_checker_.CalledOnValidThread());
 
   return context_gl_.get();
 }
 
@@ skipping 78 matching lines @@
   DCHECK(memory_policy_changed_callback_.is_null() || cb.is_null());
   memory_policy_changed_callback_ = cb;
 }
 
 void TestContextProvider::SetMaxTransferBufferUsageBytes(
     size_t max_transfer_buffer_usage_bytes) {
   context3d_->SetMaxTransferBufferUsageBytes(max_transfer_buffer_usage_bytes);
 }
 
 }  // namespace cc