Use GpuPreferences to avoid directly accessing switches in gpu related code

content/browser/android/synchronous_compositor_base.cc

 // Copyright 2015 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 "content/browser/android/synchronous_compositor_base.h"
 
 #include "base/command_line.h"
 #include "base/supports_user_data.h"
 #include "content/browser/android/in_process/synchronous_compositor_factory_impl.h"
 #include "content/browser/android/in_process/synchronous_compositor_impl.h"
 #include "content/browser/android/synchronous_compositor_host.h"
 #include "content/browser/gpu/gpu_process_host.h"
 #include "content/browser/web_contents/web_contents_android.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/gpu/in_process_gpu_thread.h"
 #include "content/public/common/content_switches.h"
 
 namespace content {
 
 class SynchronousCompositorClient;
 
 namespace {
 
+const gpu::GpuPreferences* g_gpu_preferences = nullptr;

[boliu, 2016/02/26 22:17:32]

LazyInstance<gpu::GpuPreferences>, also const won't compile

[Peng, 2016/02/29 16:09:22]

I don't see why need LazyInstance. But anyway, I removed g_gpu_preferences &
g_sync_point_manager by using a pointer of the g_gpu_service.

Done

 gpu::SyncPointManager* g_sync_point_manager = nullptr;
 
 base::Thread* CreateInProcessGpuThreadForSynchronousCompositor(
     const InProcessChildThreadParams& params) {
   DCHECK(g_sync_point_manager);
-  return new InProcessGpuThread(params, g_sync_point_manager);
+  return new InProcessGpuThread(params, g_gpu_preferences,
+                                g_sync_point_manager);
 }
 
 }  // namespace
 
 void SynchronousCompositor::SetGpuService(
     scoped_refptr<gpu::InProcessCommandBuffer::Service> service) {
+  DCHECK(!g_gpu_preferences);
   DCHECK(!g_sync_point_manager);
+  g_gpu_preferences = &service->gpu_preferences();
   g_sync_point_manager = service->sync_point_manager();
   GpuProcessHost::RegisterGpuMainThreadFactory(
       CreateInProcessGpuThreadForSynchronousCompositor);
 }
 
 // static
 void SynchronousCompositor::SetClientForWebContents(
     WebContents* contents,
     SynchronousCompositorClient* client) {
   DCHECK(contents);
@@ skipping 20 matching lines @@
         command_line->HasSwitch(switches::kSingleProcess);
     return make_scoped_ptr(new SynchronousCompositorHost(
         rwhva, web_contents_android->synchronous_compositor_client(),
         use_in_proc_software_draw));
   }
   return make_scoped_ptr(new SynchronousCompositorImpl(
       rwhva, web_contents_android->synchronous_compositor_client()));
 }
 
 }  // namespace content