Tweak priorities of paint invalidation reasons

third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h

Index: third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h
diff --git a/third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h b/third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h
index d13d195f65593320b43bd422d644a23bef64fa63..38b377d63e1384e663d4c4a24313c08e1ae30d8f 100644
--- a/third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h
+++ b/third_party/WebKit/Source/core/paint/ObjectPaintInvalidator.h
@@ -27,15 +27,16 @@ public:
     PaintInvalidationReason computePaintInvalidationReason();
     PaintInvalidationReason invalidatePaintIfNeededWithComputedReason(PaintInvalidationReason);
 
-private:
-    void invalidateSelectionIfNeeded(PaintInvalidationReason);
-
     // This function tries to minimize the amount of invalidation generated by invalidating the "difference" between
     // |m_context.oldBounds| and |m_context.newBounds|. This means invalidating the union of the previous rectangles
     // but not their intersection. The use case is when an element only requires a paint invalidation (which means
     // that its content didn't change) and its bounds changed but its location didn't.
     // If we don't meet the criteria for an incremental paint, the alternative is a full paint invalidation.
-    void incrementallyInvalidatePaint();
+    // Returns true if any paint invalidation is done.
+    bool incrementallyInvalidatePaint();
+
+private:
+    void invalidateSelectionIfNeeded(PaintInvalidationReason);
 
     // This function generates a full invalidation, which means invalidating both |oldBounds| and |newBounds|.
     // This is the default choice when generating an invalidation, as it is always correct, albeit it may force some extra painting.