Add stable id to PaintImage.

third_party/WebKit/Source/platform/graphics/Image.cpp

Index: third_party/WebKit/Source/platform/graphics/Image.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/Image.cpp b/third_party/WebKit/Source/platform/graphics/Image.cpp
index 8af49d6721cc861d07342dd7c231efe26879dcb1..be2a1d1525ceb304ff6628014244171ae1a12fbe 100644
--- a/third_party/WebKit/Source/platform/graphics/Image.cpp
+++ b/third_party/WebKit/Source/platform/graphics/Image.cpp
@@ -52,7 +52,9 @@
 namespace blink {
 
 Image::Image(ImageObserver* observer)
-    : image_observer_disabled_(false), image_observer_(observer) {}
+    : image_observer_disabled_(false),
+      image_observer_(observer),
+      stable_image_id_(PaintImage::GetNextId()) {}
 
 Image::~Image() {}
 
@@ -297,7 +299,8 @@ void Image::DrawPattern(GraphicsContext& context,
   auto image_id = image.sk_image()->uniqueID();
 
   image =
-      PaintImage(image.sk_image()->makeSubset(EnclosingIntRect(norm_src_rect)),
+      PaintImage(stable_image_id_,
+                 image.sk_image()->makeSubset(EnclosingIntRect(norm_src_rect)),
                  image.animation_type(), image.completion_state());
   if (!image)
     return;
@@ -345,7 +348,8 @@ PaintImage Image::PaintImageForCurrentFrame() {
   auto completion_state = CurrentFrameIsComplete()
                               ? PaintImage::CompletionState::DONE
                               : PaintImage::CompletionState::PARTIALLY_DONE;
-  return PaintImage(ImageForCurrentFrame(), animation_type, completion_state);
+  return PaintImage(stable_image_id_, ImageForCurrentFrame(), animation_type,
+                    completion_state);
 }
 
 bool Image::ApplyShader(PaintFlags& flags, const SkMatrix& local_matrix) {