DevTools: report adding mutation event listener as a violations.

third_party/WebKit/Source/core/events/EventUtil.cpp

Index: third_party/WebKit/Source/core/events/EventUtil.cpp
diff --git a/third_party/WebKit/Source/core/events/EventUtil.cpp b/third_party/WebKit/Source/core/events/EventUtil.cpp
index 96588ab7302f0e21ad0adcd53ccfbc27074ea445..1b2df29ed6f5ab0a61a8d09a70e119c14165fa1e 100644
--- a/third_party/WebKit/Source/core/events/EventUtil.cpp
+++ b/third_party/WebKit/Source/core/events/EventUtil.cpp
@@ -23,6 +23,15 @@ bool IsPointerEventType(const AtomicString& event_type) {
          event_type == EventTypeNames::pointerup;
 }
 
+bool IsDOMMutationEventType(const AtomicString& event_type) {
+  return event_type == EventTypeNames::DOMCharacterDataModified ||
+         event_type == EventTypeNames::DOMNodeInserted ||
+         event_type == EventTypeNames::DOMNodeInsertedIntoDocument ||
+         event_type == EventTypeNames::DOMNodeRemoved ||
+         event_type == EventTypeNames::DOMNodeRemovedFromDocument ||
+         event_type == EventTypeNames::DOMSubtreeModified;
+}
+
 }  // namespace eventUtil
 
 }  // namespace blink