Provide TaskRunner to ContextCacheController

cc/output/context_cache_controller.h

 // Copyright (c) 2016 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.
 
 #ifndef CC_OUTPUT_CONTEXT_CACHE_CONTROLLER_H_
 #define CC_OUTPUT_CONTEXT_CACHE_CONTROLLER_H_
 
 #include <cstdint>
 #include <memory>
 
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "cc/base/cc_export.h"
 
 class GrContext;
 
+namespace base {
+class SingleThreadTaskRunner;
+}
+
 namespace gpu {
 class ContextSupport;
 }
 
 namespace cc {
 
 // ContextCacheController manages clearing cached data on ContextProvider when
 // appropriate. Currently, cache clearing happens when the ContextProvider
 // transitions from visible to not visible. As a ContextProvider may have
 // multiple clients, ContextCacheController tracks visibility across all
 // clients and only cleans up when appropriate.
 //
 // Note: Virtuals on this function are for testing only. This function is not
 // designed to have multiple implementations.
 class CC_EXPORT ContextCacheController {
  public:
   class CC_EXPORT ScopedVisibility {
    public:
     ~ScopedVisibility();
 
    private:
     friend class ContextCacheController;
     ScopedVisibility();
     void Release();
 
     bool released_ = false;
   };
 
-  explicit ContextCacheController(gpu::ContextSupport* context_support);
+  ContextCacheController(
+      gpu::ContextSupport* context_support,
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   virtual ~ContextCacheController();
 
   void SetGrContext(GrContext* gr_context);
 
   // Clients of the owning ContextProvider should call this function when they
   // become visible. The returned ScopedVisibility pointer must be passed back
   // to ClientBecameNotVisible or it will DCHECK in its destructor.
   virtual std::unique_ptr<ScopedVisibility> ClientBecameVisible();
 
   // When a client becomes not visible (either due to a visibility change or
   // because it is being deleted), it must pass back any ScopedVisibility
   // pointers it owns via this function.
   virtual void ClientBecameNotVisible(
       std::unique_ptr<ScopedVisibility> scoped_visibility);
 
  protected:
   std::unique_ptr<ScopedVisibility> CreateScopedVisibilityForTesting() const;
   void ReleaseScopedVisibilityForTesting(
       std::unique_ptr<ScopedVisibility> scoped_visibility) const;
 
  private:
   gpu::ContextSupport* context_support_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;

[danakj, 2016/09/19 18:59:17]

Remind me why this is here? It's not used.

[ericrk, 2016/09/19 20:00:27]

I'm going to use it in a follow-up CL I'll send after this.

   GrContext* gr_context_ = nullptr;
 
   uint32_t num_clients_visible_ = 0;
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_CONTEXT_CACHE_CONTROLLER_H_