Paint invalidation tests for slimming paint v2

Source/core/testing/Internals.idl

Index: Source/core/testing/Internals.idl
diff --git a/Source/core/testing/Internals.idl b/Source/core/testing/Internals.idl
index 4b24aaf839bd080d0210ac3cb87fc1da0434dab6..e6627a167b6eae2f39ffe4d97a5f91722fce13f0 100644
--- a/Source/core/testing/Internals.idl
+++ b/Source/core/testing/Internals.idl
@@ -230,8 +230,9 @@
 
     DOMString[] getReferencedFilePaths();
 
-    // These functions both reset the tracked repaint rects. They are inteded to be used in the following order:
-    //  startTrackingRepaints, repaintRectsAsText, stopTrackingRepaints.
+    // These functions both reset the tracked repaint rects. They are intended to be used in the following order:
+    //  startTrackingRepaints(), repaintRectsAsText(), stopTrackingRepaints().
+    // TODO(wangxianzhu): Remove these functions when we no longer use repaint rects.
     [RaisesException, TypeChecking=Interface] void startTrackingRepaints(Document document);
     [RaisesException, TypeChecking=Interface] void stopTrackingRepaints(Document document);
 
@@ -242,6 +243,16 @@
 
     [RaisesException, TypeChecking=Interface] void forceFullRepaint(Document document);
 
+    // These functions both reset the tracked paint invalidation objects. They are intended to be used in the following order:
+    //  startTrackingPaintInvalidationObjects(), trackedPaintInvalidationObjects(), stopTrackingPaintInvalidationObjects().
+    void startTrackingPaintInvalidationObjects();
+    void stopTrackingPaintInvalidationObjects();
+
+    // Returns a list of debug strings for objects that were invalidated between
+    // startTrackingPaintInvalidationObjects() and stopTrackingPaintInvalidationObjects().
+    // If an object is invalidated multiple times, it will appear in the list multiple times.
+    DOMString[] trackedPaintInvalidationObjects();
+
     // Returns a list of draggable/non-draggable regions in the document.
     [RaisesException, TypeChecking=Interface] ClientRectList draggableRegions(Document document);
     [RaisesException, TypeChecking=Interface] ClientRectList nonDraggableRegions(Document document);