services/ui: Use a gpu::GpuChannelHost when creating ui::OutputSurface.

services/ui/public/cpp/context_provider.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 "services/ui/public/cpp/context_provider.h"
 
 #include <stdint.h>
 
 #include "base/logging.h"
+#include "gpu/ipc/client/gpu_channel_host.h"
 #include "services/ui/public/cpp/gles2_context.h"
 
 namespace ui {
 
-ContextProvider::ContextProvider(GpuService* gpu_service)
-    : gpu_service_(gpu_service) {}
+ContextProvider::ContextProvider(
+    scoped_refptr<gpu::GpuChannelHost> gpu_channel_host)
+    : gpu_channel_host_(std::move(gpu_channel_host)) {}
 
 bool ContextProvider::BindToCurrentThread() {
-  context_ = GLES2Context::CreateOffscreenContext(gpu_service_);
+  context_ = GLES2Context::CreateOffscreenContext(gpu_channel_host_);
   return !!context_;
 }
 
 gpu::gles2::GLES2Interface* ContextProvider::ContextGL() {
   return context_->interface();
 }
 
 gpu::ContextSupport* ContextProvider::ContextSupport() {
   if (!context_)
     return NULL;
@@ skipping 17 matching lines @@
 base::Lock* ContextProvider::GetLock() {
   // This context provider is not used on multiple threads.
   NOTREACHED();
   return nullptr;
 }
 
 ContextProvider::~ContextProvider() {
 }
 
 }  // namespace ui