Move frame eviction into components

components/viz/frame_sinks/frame_evictor.h

+// Copyright 2017 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 COMPONENTS_VIZ_FRAME_SINKS_FRAME_EVICTOR_H_
+#define COMPONENTS_VIZ_FRAME_SINKS_FRAME_EVICTOR_H_
+
+#include "base/macros.h"
+#include "components/viz/frame_sinks/frame_eviction_manager.h"
+#include "components/viz/frame_sinks/viz_export.h"
+
+namespace viz {
+
+class VIZ_EXPORT FrameEvictorClient {
+ public:
+  virtual ~FrameEvictorClient() {}
+  virtual void EvictDelegatedFrame() = 0;
+};
+
+class VIZ_EXPORT FrameEvictor : public FrameEvictionManagerClient {
+ public:
+  // |client| must outlive |this|.
+  explicit FrameEvictor(FrameEvictorClient* client);
+  ~FrameEvictor() override;
+
+  void SwappedFrame(bool visible);
+  void DiscardedFrame();
+  void SetVisible(bool visible);
+  void LockFrame();
+  void UnlockFrame();
+  bool HasFrame() { return has_frame_; }
+
+ private:
+  // FrameEvictionManagerClient implementation.
+  void EvictCurrentFrame() override;
+
+  FrameEvictorClient* client_;
+  bool has_frame_;
+  bool visible_;
+
+  DISALLOW_COPY_AND_ASSIGN(FrameEvictor);
+};
+
+}  // namespace viz
+
+#endif  // COMPONENTS_VIZ_FRAME_SINKS_FRAME_EVICTOR_H_