Prevent default actions for JS-generated mouse events other than click

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index aa67a5ea3fc523d3fff4d823531b89ee4e66fac3..b8e9cbc61c6377e69b2d57449986df40067fc249 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -2102,8 +2102,10 @@ void Node::dispatchScopedEventDispatchMediator(PassRefPtrWillBeRawPtr<EventDispa
 
 bool Node::dispatchEvent(PassRefPtrWillBeRawPtr<Event> event)
 {
-    if (event->isMouseEvent())
-        return EventDispatcher::dispatchEvent(*this, MouseEventDispatchMediator::create(static_pointer_cast<MouseEvent>(event), MouseEventDispatchMediator::SyntheticMouseEvent));
+    if (event->isMouseEvent()) {
+        toMouseEvent(*event).setFromScript();
+        return dispatchMouseEvent(static_pointer_cast<MouseEvent>(event));
+    }
     if (event->isTouchEvent())
         return dispatchTouchEvent(static_pointer_cast<TouchEvent>(event));
     return EventDispatcher::dispatchEvent(*this, EventDispatchMediator::create(event));
@@ -2142,6 +2144,11 @@ bool Node::dispatchMouseEvent(const PlatformMouseEvent& event, const AtomicStrin
     return EventDispatcher::dispatchEvent(*this, MouseEventDispatchMediator::create(MouseEvent::create(eventType, document().domWindow(), event, detail, relatedTarget)));
 }
 
+bool Node::dispatchMouseEvent(PassRefPtrWillBeRawPtr<MouseEvent> event)
+{
+    return EventDispatcher::dispatchEvent(*this, MouseEventDispatchMediator::create(event));
+}
+
 bool Node::dispatchGestureEvent(const PlatformGestureEvent& event)
 {
     RefPtrWillBeRawPtr<GestureEvent> gestureEvent = GestureEvent::create(document().domWindow(), event);