android: add ThumbnailCache

chrome/browser/android/thumbnail/thumbnail.h

+// 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.
+
+#ifndef CHROME_BROWSER_ANDROID_THUMBNAIL_THUMBNAIL_H_
+#define CHROME_BROWSER_ANDROID_THUMBNAIL_THUMBNAIL_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+#include "cc/resources/ui_resource_bitmap.h"
+#include "cc/resources/ui_resource_client.h"
+#include "content/public/browser/android/ui_resource_client_android.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace base {
+class Time;
+}
+
+namespace content {
+class UIResourceProvider;
+}
+
+namespace gfx {
+class Size;
+}
+
+typedef int TabId;
+
+class Thumbnail;
+
+class ThumbnailDelegate {
+ public:
+  virtual void InvalidateCachedThumbnail(Thumbnail* thumbnail) = 0;
+  virtual ~ThumbnailDelegate() {}
+};
+
+class Thumbnail : public content::UIResourceClientAndroid {
+ public:
+  static scoped_ptr<Thumbnail> Create(
+      TabId tab_id,
+      const base::Time& time_stamp,
+      float scale,
+      content::UIResourceProvider* ui_resource_provider,
+      ThumbnailDelegate* thumbnail_delegate);
+  virtual ~Thumbnail();
+
+  TabId tab_id() const { return tab_id_; }
+  base::Time time_stamp() const { return time_stamp_; }
+  float scale() const { return scale_; }
+  cc::UIResourceId ui_resource_id() const { return ui_resource_id_; }
+  const gfx::SizeF& scaled_content_size() const { return scaled_content_size_; }
+  const gfx::SizeF& scaled_data_size() const { return scaled_data_size_; }
+
+  void SetBitmap(const SkBitmap& bitmap);
+  void SetCompressedBitmap(skia::RefPtr<SkPixelRef> compressed_bitmap,
+                           const gfx::Size& content_size);
+  void CreateUIResource();
+
+  // content::UIResourceClient implementation.
+  virtual cc::UIResourceBitmap GetBitmap(cc::UIResourceId uid,
+                                         bool resource_lost) OVERRIDE;
+
+  // content::UIResourceClientAndroid implementation.
+  virtual void UIResourceIsInvalid() OVERRIDE;
+
+ protected:
+  Thumbnail(TabId tab_id,
+            const base::Time& time_stamp,
+            float scale,
+            content::UIResourceProvider* ui_resource_provider,
+            ThumbnailDelegate* thumbnail_delegate);
+
+  void ClearUIResourceId();
+
+  TabId tab_id_;
+  base::Time time_stamp_;
+  float scale_;
+
+  gfx::SizeF scaled_content_size_;
+  gfx::SizeF scaled_data_size_;
+
+  cc::UIResourceBitmap bitmap_;
+  cc::UIResourceId ui_resource_id_;
+
+  bool retrieved_;
+
+  content::UIResourceProvider* ui_resource_provider_;
+  ThumbnailDelegate* thumbnail_delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(Thumbnail);
+};
+
+#endif  // CHROME_BROWSER_ANDROID_THUMBNAIL_THUMBNAIL_H_