Skipping mouseenter/over/out/leave on deleted nodes.

Source/core/input/EventHandler.cpp

Index: Source/core/input/EventHandler.cpp
diff --git a/Source/core/input/EventHandler.cpp b/Source/core/input/EventHandler.cpp
index c66e5f02b6f1e0f58f7b3f1b30dacd77b3fc7a9b..c91483f2906b449b09eb22d43beb0b5db80f9aca 100644
--- a/Source/core/input/EventHandler.cpp
+++ b/Source/core/input/EventHandler.cpp
@@ -1526,7 +1526,7 @@ void EventHandler::sendMouseEventsForNodeTransition(Node* exitedNode, Node* ente
     ASSERT(exitedNode != enteredNode);
 
     // First, dispatch mouseout event (which bubbles to ancestors)
-    if (exitedNode)
+    if (exitedNode && exitedNode->inDocument())

[dtapuska, 2015/08/14 17:20:09]

Can we just make an anonymous scope function to check this?

bool isNodeInDocument(Node* n) {
   return n && n->inDocument();
}

instead of repeating it a few times?

[mustaq, 2015/08/14 21:00:15]

Done.

         exitedNode->dispatchMouseEvent(mouseEvent, EventTypeNames::mouseout, 0, enteredNode);
 
     // A note on mouseenter and mouseleave: These are non-bubbling events, and they are dispatched if there
@@ -1546,13 +1546,13 @@ void EventHandler::sendMouseEventsForNodeTransition(Node* exitedNode, Node* ente
     // Create lists of all exited/entered ancestors.
     WillBeHeapVector<RefPtrWillBeMember<Node>, 32> exitedAncestors;
     WillBeHeapVector<RefPtrWillBeMember<Node>, 32> enteredAncestors;
-    if (exitedNode) {
+    if (exitedNode && exitedNode->inDocument()) {
         exitedNode->updateDistribution();
         for (Node* node = exitedNode; node; node = ComposedTreeTraversal::parent(*node)) {
             exitedAncestors.append(node);
         }
     }
-    if (enteredNode) {
+    if (enteredNode && enteredNode->inDocument()) {
         enteredNode->updateDistribution();
         for (Node* node = enteredNode; node; node = ComposedTreeTraversal::parent(*node)) {
             enteredAncestors.append(node);
@@ -1591,7 +1591,7 @@ void EventHandler::sendMouseEventsForNodeTransition(Node* exitedNode, Node* ente
     }
 
     // Dispatch mouseover event (which bubbles to ancestors) after the mouseleave events are sent.
-    if (enteredNode)
+    if (enteredNode && enteredNode->inDocument())
         enteredNode->dispatchMouseEvent(mouseEvent, EventTypeNames::mouseover, 0, exitedNode);
 
     // Determine if there is a capturing mouseenter listener in an ancestor. This must be done /after/ dispatching the