Android: Don't destroy LayerTreeHost when Surface goes away

chrome/browser/android/thumbnail/thumbnail_cache.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_CACHE_H_
 #define CHROME_BROWSER_ANDROID_THUMBNAIL_THUMBNAIL_CACHE_H_
 
 #include <list>
 #include <set>
 #include <string>
 
 #include "base/bind.h"
 #include "base/containers/hash_tables.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
 #include "base/time/time.h"
 #include "chrome/browser/android/thumbnail/scoped_ptr_expiring_cache.h"
 #include "chrome/browser/android/thumbnail/thumbnail.h"
 #include "third_party/skia/include/core/SkBitmap.h"
-#include "ui/android/resources/ui_resource_client_android.h"
 #include "ui/android/resources/ui_resource_provider.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/size_f.h"
 #include "url/gurl.h"
 
 namespace base {
 class File;
 class Time;
 }
@@ skipping 31 matching lines @@
 
   void RemoveFromDiskAtAndAboveId(TabId min_id);
   void InvalidateThumbnailIfChanged(TabId tab_id, const GURL& url);
   bool CheckAndUpdateThumbnailMetaData(TabId tab_id, const GURL& url);
   void UpdateVisibleIds(const TabIdList& priority);
   void DecompressThumbnailFromFile(
       TabId tab_id,
       const base::Callback<void(bool, SkBitmap)>&
           post_decompress_callback);
 
+  // Called when resident textures were evicted, which requires paging
+  // in bitmaps.
+  void OnUIResourcesWereEvicted();
+
   // ThumbnailDelegate implementation
   void InvalidateCachedThumbnail(Thumbnail* thumbnail) override;
   static base::FilePath GetCacheDirectory();
   static base::FilePath GetFilePath(TabId tab_id);
 
  private:
   class ThumbnailMetaData {
    public:
     ThumbnailMetaData();
     ThumbnailMetaData(const base::Time& current_time, const GURL& url);
@@ skipping 75 matching lines @@
   TabIdList visible_ids_;
 
   ui::UIResourceProvider* ui_resource_provider_;
 
   base::WeakPtrFactory<ThumbnailCache> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ThumbnailCache);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_THUMBNAIL_THUMBNAIL_CACHE_H_