Fix unscrollable scrollers after closing a <dialog>.

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index 6152fa9e3b9a2a33df438d9be6b6be6d076513e4..574a3df28769d42eee63a695947c54ab8498a2dd 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -3605,6 +3605,11 @@ class CORE_EXPORT ComputedStyle : public ComputedStyleBase,
     return overflowY() == OverflowPagedX || overflowY() == OverflowPagedY;
   }
 
+  // Visibility utility functions.
+  bool visibleToHitTesting() const {
+    return visibility() == EVisibility::Visible && pointerEvents() != PE_NONE;
+  }
+
   // Animation utility functions.
   bool shouldCompositeForCurrentAnimations() const {
     return hasCurrentOpacityAnimation() || hasCurrentTransformAnimation() ||