(not for commit) Create 2nd ContextProvider for Ganesh rasterization.

cc/output/overlay_unittest.cc

 // Copyright 2014 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/base/scoped_ptr_vector.h"
 #include "cc/output/gl_renderer.h"
 #include "cc/output/output_surface.h"
 #include "cc/output/output_surface_client.h"
 #include "cc/output/overlay_candidate_validator.h"
 #include "cc/output/overlay_processor.h"
@@ skipping 82 matching lines @@
     ResourceProvider* resource_provider)
     : OverlayProcessor(surface, resource_provider) {}
 
 size_t DefaultOverlayProcessor::GetStrategyCount() {
   return strategies_.size();
 }
 
 class OverlayOutputSurface : public OutputSurface {
  public:
   explicit OverlayOutputSurface(scoped_refptr<ContextProvider> context_provider)
-      : OutputSurface(context_provider) {}
+      : OutputSurface(context_provider, scoped_refptr<ContextProvider>()) {}
 
   // OutputSurface implementation
   void SwapBuffers(CompositorFrame* frame) override;
 
   void InitWithSingleOverlayValidator() {
     overlay_candidate_validator_.reset(new SingleOverlayValidator);
   }
 };
 
 void OverlayOutputSurface::SwapBuffers(CompositorFrame* frame) {
@@ skipping 693 matching lines @@
   renderer_->BeginDrawingFrame(&frame3);
   renderer_->FinishDrawingFrame(&frame3);
   EXPECT_TRUE(resource_provider_->InUseByConsumer(resource1));
   SwapBuffers();
   EXPECT_FALSE(resource_provider_->InUseByConsumer(resource1));
   Mock::VerifyAndClearExpectations(&scheduler_);
 }
 
 }  // namespace
 }  // namespace cc