Refactor client visibility handling

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 "cc/output/context_cache_controller.h"
 #include "gpu/ipc/client/gpu_channel_host.h"
 #include "services/ui/public/cpp/gles2_context.h"
 
 namespace ui {
 
 ContextProvider::ContextProvider(
     scoped_refptr<gpu::GpuChannelHost> gpu_channel_host)
     : gpu_channel_host_(std::move(gpu_channel_host)) {}
 
 bool ContextProvider::BindToCurrentThread() {
   context_ = GLES2Context::CreateOffscreenContext(gpu_channel_host_);
+  cache_controller_.reset(
+      new cc::ContextCacheController(context_->context_support()));
   return !!context_;

[danakj, 2016/08/26 23:49:09]

This suggests context_ can be null. Either your code will crash or this should
just return true.

[ericrk, 2016/08/29 22:43:23]

Yeah, it can be null, good point.

 }
 
 gpu::gles2::GLES2Interface* ContextProvider::ContextGL() {
   return context_->interface();
 }
 
 gpu::ContextSupport* ContextProvider::ContextSupport() {
   if (!context_)
     return NULL;
   return context_->context_support();
 }
 
 class GrContext* ContextProvider::GrContext() {
   return NULL;
 }
 
+cc::ContextCacheController* ContextProvider::CacheController() {
+  return cache_controller_.get();
+}
+
 void ContextProvider::InvalidateGrContext(uint32_t state) {}
 
 gpu::Capabilities ContextProvider::ContextCapabilities() {
   gpu::Capabilities capabilities;
   // Enabled the CHROMIUM_image extension to use GpuMemoryBuffers. The
   // implementation of which is used in CommandBufferDriver.
   capabilities.image = true;
   return capabilities;
 }
 
 base::Lock* ContextProvider::GetLock() {
   // This context provider is not used on multiple threads.
   NOTREACHED();
   return nullptr;
 }
 
 ContextProvider::~ContextProvider() {
 }
 
 }  // namespace ui