cc: Update discardable image metadata generation to get PaintImages.

cc/paint/discardable_image_store.h

Index: cc/paint/discardable_image_store.h
diff --git a/cc/paint/discardable_image_store.h b/cc/paint/discardable_image_store.h
new file mode 100644
index 0000000000000000000000000000000000000000..1c26e79e57653e22e29435d7492ba40f4fceb81c
--- /dev/null
+++ b/cc/paint/discardable_image_store.h
@@ -0,0 +1,51 @@
+// 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 CC_PAINT_DISCARDABLE_IMAGE_STORE_H_
+#define CC_PAINT_DISCARDABLE_IMAGE_STORE_H_
+
+#include "base/containers/flat_map.h"
+#include "cc/paint/draw_image.h"
+#include "cc/paint/image_id.h"
+#include "cc/paint/paint_export.h"
+#include "cc/paint/paint_op_buffer.h"
+#include "third_party/skia/include/core/SkMatrix.h"
+#include "third_party/skia/include/core/SkRect.h"
+#include "third_party/skia/include/utils/SkNoDrawCanvas.h"
+
+namespace cc {
+class PaintFlags;
+class PaintImage;
+
+class CC_PAINT_EXPORT DiscardableImageStore {
+ public:
+  DiscardableImageStore(int width,
+                        int height,
+                        std::vector<std::pair<DrawImage, gfx::Rect>>* image_set,
+                        base::flat_map<ImageId, gfx::Rect>* image_id_to_rect);
+  ~DiscardableImageStore();
+
+  void GatherDiscardableImages(const PaintOpBuffer* buffer);
+  SkNoDrawCanvas* GetNoDrawCanvas();
+
+ private:
+  class PaintTrackingCanvas;
+
+  void AddImageFromFlags(const SkRect& rect, const PaintFlags& flags);
+  void AddImage(const PaintImage& paint_image,
+                const SkRect& src_rect,
+                const SkRect& rect,
+                const SkMatrix* local_matrix,
+                const PaintFlags& flags);
+
+  // This canvas is used only for tracking transform/clip/filter state from the
+  // non-drawing ops.
+  std::unique_ptr<PaintTrackingCanvas> canvas_;
+  std::vector<std::pair<DrawImage, gfx::Rect>>* image_set_;
+  base::flat_map<ImageId, gfx::Rect>* image_id_to_rect_;
+};
+
+}  // namespace cc
+
+#endif  // CC_PAINT_DISCARDABLE_IMAGE_STORE_H_