Avoid firing load events on style elements if there is no listeners for that

third_party/WebKit/Source/core/dom/Document.cpp

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index 829e3b3faa55811409cef1770422e02e4a5a54e8..ca1ee1e1153cf75966e472cae99e65fc87446542 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -4593,7 +4593,8 @@ void Document::AddMutationEventListenerTypeIfEnabled(
     AddListenerType(listener_type);
 }
 
-void Document::AddListenerTypeIfNeeded(const AtomicString& event_type) {
+void Document::AddListenerTypeIfNeeded(const AtomicString& event_type,
+                                       EventTarget& event_target) {
   if (event_type == EventTypeNames::DOMSubtreeModified) {
     UseCounter::Count(*this, UseCounter::kDOMSubtreeModifiedEvent);
     AddMutationEventListenerTypeIfEnabled(DOMSUBTREEMODIFIED_LISTENER);
@@ -4630,6 +4631,15 @@ void Document::AddListenerTypeIfNeeded(const AtomicString& event_type) {
     AddListenerType(TRANSITIONEND_LISTENER);
   } else if (event_type == EventTypeNames::scroll) {
     AddListenerType(SCROLL_LISTENER);
+  } else if (event_type == EventTypeNames::load) {
+    if (Node* node = event_target.ToNode()) {
+      if (isHTMLStyleElement(*node)) {
+        AddListenerType(LOAD_LISTENER_AT_CAPTURE_PHASE_OR_AT_STYLE_ELEMENT);
+        return;
+      }
+    }
+    if (event_target.HasCapturingEventListeners(event_type))
+      AddListenerType(LOAD_LISTENER_AT_CAPTURE_PHASE_OR_AT_STYLE_ELEMENT);
   }
 }