Move frame eviction into components

components/display_compositor/renderer_frame_manager.h

 // Copyright 2013 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 CONTENT_BROWSER_RENDERER_HOST_RENDERER_FRAME_MANAGER_H_
-#define CONTENT_BROWSER_RENDERER_HOST_RENDERER_FRAME_MANAGER_H_
+#ifndef COMPONENTS_DISPLAY_COMPOSITOR_RENDERER_FRAME_MANAGER_H_
+#define COMPONENTS_DISPLAY_COMPOSITOR_RENDERER_FRAME_MANAGER_H_
 
 #include <stddef.h>
 
 #include <list>
 #include <map>
 
 #include "base/macros.h"
 #include "base/memory/memory_coordinator_client.h"
 #include "base/memory/memory_pressure_listener.h"
 #include "base/memory/singleton.h"
-#include "content/common/content_export.h"
+#include "components/display_compositor/display_compositor_export.h"
 
-namespace content {
+namespace display_compositor {
 
-class RenderWidgetHostViewAuraTest;
-
-class CONTENT_EXPORT RendererFrameManagerClient {
+class DISPLAY_COMPOSITOR_EXPORT RendererFrameManagerClient {
  public:
   virtual ~RendererFrameManagerClient() {}
   virtual void EvictCurrentFrame() = 0;
 };
 
 // This class is responsible for globally managing which renderers keep their
 // compositor frame when offscreen. We actively discard compositor frames for
 // offscreen tabs, but keep a minimum amount, as an LRU cache, to make switching
 // between a small set of tabs faster. The limit is a soft limit, because
 // clients can lock their frame to prevent it from being discarded, e.g. if the
 // tab is visible, or while capturing a screenshot.
-class CONTENT_EXPORT RendererFrameManager :
-    public base::MemoryCoordinatorClient {
+class DISPLAY_COMPOSITOR_EXPORT RendererFrameManager

[Saman Sami, 2017/04/11 14:58:24]

I think this class should have a more general name such as FrameEvictionManager
because renderer is not a thing in the display compositor and also eventually
this class manages all frames not just those that come from the renderer.

[xing.xu, 2017/04/14 03:01:29]

Done.

+    : public base::MemoryCoordinatorClient {
  public:
   static RendererFrameManager* GetInstance();
 
   void AddFrame(RendererFrameManagerClient*, bool locked);
   void RemoveFrame(RendererFrameManagerClient*);
   void LockFrame(RendererFrameManagerClient*);
   void UnlockFrame(RendererFrameManagerClient*);
 
   size_t GetMaxNumberOfSavedFrames() const;
 
   // For testing only
   void set_max_number_of_saved_frames(size_t max_number_of_saved_frames) {
     max_number_of_saved_frames_ = max_number_of_saved_frames;
   }
   void set_max_handles(float max_handles) { max_handles_ = max_handles; }
 
+  // React on memory pressure events to adjust the number of cached frames.
+  // Please remove when crbug.com/443824 has been fixed.
+  void OnMemoryPressure(
+      base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level);
+
  private:
-  // Please remove when crbug.com/443824 has been fixed.
-  friend class RenderWidgetHostViewAuraTest;
-
   RendererFrameManager();
   ~RendererFrameManager() override;
 
   // base::MemoryCoordinatorClient implementation:
   void OnPurgeMemory() override;
 
   void CullUnlockedFrames(size_t saved_frame_limit);
 
-  // React on memory pressure events to adjust the number of cached frames.
-  void OnMemoryPressure(
-      base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level);
-
   void PurgeMemory(int percentage);
 
   friend struct base::DefaultSingletonTraits<RendererFrameManager>;
 
   // Listens for system under pressure notifications and adjusts number of
   // cached frames accordingly.
   std::unique_ptr<base::MemoryPressureListener> memory_pressure_listener_;
 
   std::map<RendererFrameManagerClient*, size_t> locked_frames_;
   std::list<RendererFrameManagerClient*> unlocked_frames_;
   size_t max_number_of_saved_frames_;
   float max_handles_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererFrameManager);
 };
 
-}  // namespace content
+}  // namespace display_compositor
 
-#endif  // CONTENT_BROWSER_RENDERER_HOST_RENDERER_FRAME_MANAGER_H_
+#endif  // COMPONENTS_DISPLAY_COMPOSITOR_RENDERER_FRAME_MANAGER_H_