cc: Update discardable image metadata generation to get PaintImages.

cc/paint/display_item_list.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 CC_PAINT_DISPLAY_ITEM_LIST_H_
 #define CC_PAINT_DISPLAY_ITEM_LIST_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 145 matching lines @@
   gfx::Rect VisualRectForTesting(int index) { return visual_rects_[index]; }
 
   ContiguousContainer<DisplayItem>::const_iterator begin() const {
     return items_.begin();
   }
 
   ContiguousContainer<DisplayItem>::const_iterator end() const {
     return items_.end();
   }
 
+  void GatherDiscardableImages(DiscardableImageStore* image_store) const;
+  const DiscardableImageMap& discardable_image_map_for_testing() const {
+    return image_map_;
+  }
+
   bool has_discardable_images() const { return has_discardable_images_; }
 
  private:
   FRIEND_TEST_ALL_PREFIXES(DisplayItemListTest, AsValueWithNoItems);
   FRIEND_TEST_ALL_PREFIXES(DisplayItemListTest, AsValueWithItems);
 
   ~DisplayItemList();
 
   std::unique_ptr<base::trace_event::TracedValue> CreateTracedValue(
       bool include_items) const;
@@ skipping 32 matching lines @@
   bool has_discardable_images_ = false;
 
   friend class base::RefCountedThreadSafe<DisplayItemList>;
   FRIEND_TEST_ALL_PREFIXES(DisplayItemListTest, ApproximateMemoryUsage);
   DISALLOW_COPY_AND_ASSIGN(DisplayItemList);
 };
 
 }  // namespace cc
 
 #endif  // CC_PAINT_DISPLAY_ITEM_LIST_H_