Stopping event propagation in the default event group should not stop it for the system event group. Bug 216237, r=caillon, sr=jst, a=mkaply.

layout/base/nsPresShell.cpp

@@ -6221,6 +6221,13 @@ PresShell::HandleEventInternal(nsEvent* aEvent, nsIView *aView,
       }
 
       // Continue with second dispatch to system event handlers.
+
+      // Stopping propagation in the default group does not affect
+      // propagation in the system event group.
+      // (see also section 1.2.2.6 of the DOM3 Events Working Draft)
+
+      aEvent->flags &= ~NS_EVENT_FLAG_STOP_DISPATCH;
+
       // Need to null check mCurrentEventContent and mCurrentEventFrame
       // since the previous dispatch could have nuked them.
       if (mCurrentEventContent) {

layout/html/base/src/nsPresShell.cpp

@@ -6221,6 +6221,13 @@ PresShell::HandleEventInternal(nsEvent* aEvent, nsIView *aView,
       }
 
       // Continue with second dispatch to system event handlers.
+
+      // Stopping propagation in the default group does not affect
+      // propagation in the system event group.
+      // (see also section 1.2.2.6 of the DOM3 Events Working Draft)
+
+      aEvent->flags &= ~NS_EVENT_FLAG_STOP_DISPATCH;
+
       // Need to null check mCurrentEventContent and mCurrentEventFrame
       // since the previous dispatch could have nuked them.
       if (mCurrentEventContent) {