services/ui: Remove unwanted gpu dependency from services/ui/surfaces.

services/ui/surfaces/surfaces_context_provider.h

Index: services/ui/surfaces/surfaces_context_provider.h
diff --git a/services/ui/surfaces/surfaces_context_provider.h b/services/ui/surfaces/surfaces_context_provider.h
index 207d3db32cbfe1168a547e85b783dce95b297662..6746750e8f4a8e030fa47a60527da8df0ecb0fd3 100644
--- a/services/ui/surfaces/surfaces_context_provider.h
+++ b/services/ui/surfaces/surfaces_context_provider.h
@@ -18,6 +18,7 @@
 namespace gpu {
 
 class CommandBufferProxyImpl;
+class GpuChannelHost;
 struct GpuProcessHostedCALayerTreeParamsMac;
 class TransferBuffer;
 
@@ -41,7 +42,8 @@ class SurfacesContextProviderDelegate;
 class SurfacesContextProvider : public cc::ContextProvider,
                                 public base::NonThreadSafe {
  public:
-  explicit SurfacesContextProvider(gfx::AcceleratedWidget widget);
+  SurfacesContextProvider(gfx::AcceleratedWidget widget,
+                          scoped_refptr<gpu::GpuChannelHost> gpu_channel);
 
   void SetDelegate(SurfacesContextProviderDelegate* delegate);