cc: Keep PaintImage in DrawImage.

cc/paint/paint_image.h

Index: cc/paint/paint_image.h
diff --git a/cc/paint/paint_image.h b/cc/paint/paint_image.h
index 1dc39ae5551da64cb75a7acb57335a921bc211e2..09fe93a9502fbcd6f334001b5e1bf8da3880f0dc 100644
--- a/cc/paint/paint_image.h
+++ b/cc/paint/paint_image.h
@@ -22,6 +22,11 @@ class CC_PAINT_EXPORT PaintImage {
   // GetNextId to generate a stable id for such images.
   static const Id kNonLazyStableId = -1;
 
+  // This is the id used in places where we are currently not plumbing the
+  // correct image id from blink.
+  // TODO(khushalsagar): Eliminate these cases. See crbug.com/722559.
+  static const Id kWrongStableId = -2;

[vmpstr, 2017/05/16 17:43:27]

s/Wrong/Unknown/ and also maybe initialize id_ to this?

[Khushal, 2017/05/16 21:29:12]

Done.

+
   // TODO(vmpstr): Work towards removing "UNKNOWN" value.
   enum class AnimationType { UNKNOWN, ANIMATED, VIDEO, STATIC };
 
@@ -42,7 +47,7 @@ class CC_PAINT_EXPORT PaintImage {
   PaintImage& operator=(const PaintImage& other);
   PaintImage& operator=(PaintImage&& other);
 
-  bool operator==(const PaintImage& other);
+  bool operator==(const PaintImage& other) const;
   explicit operator bool() const { return sk_image_; }
 
   Id stable_id() const { return id_; }