Use a cc::Display for layout tests.

cc/test/pixel_test_delegating_output_surface.h

Index: cc/test/pixel_test_delegating_output_surface.h
diff --git a/cc/test/pixel_test_delegating_output_surface.h b/cc/test/pixel_test_delegating_output_surface.h
index b4686461f49caea40652e2c90041a42255dd2290..5d04f977239ac19472813228b04e7e5480cefad6 100644
--- a/cc/test/pixel_test_delegating_output_surface.h
+++ b/cc/test/pixel_test_delegating_output_surface.h
@@ -23,6 +23,7 @@ class PixelTestDelegatingOutputSurface : public OutputSurface,
   PixelTestDelegatingOutputSurface(
       scoped_refptr<ContextProvider> compositor_context_provider,
       scoped_refptr<ContextProvider> worker_context_provider,
+      scoped_refptr<ContextProvider> display_context_provider,
       SharedBitmapManager* shared_bitmap_manager,
       gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
       bool allow_force_reclaim_resources,
@@ -57,6 +58,9 @@ class PixelTestDelegatingOutputSurface : public OutputSurface,
   const bool allow_force_reclaim_resources_;
   const bool synchronous_composite_;
 
+  // Passed to the Display.
+  scoped_refptr<ContextProvider> display_context_provider_;
+
   gfx::Size enlarge_pass_texture_amount_;
 
   // TODO(danakj): These don't to be stored in unique_ptrs when OutputSurface