This is a potential regression of the fix for 7142565. The method [AWTView deliverJavaKeyEventHelper] uses a pointer to the latest key event in order to compare current key event with the previous one. In case the pointers are equal current event is ignored.
However, as the pointer doesn't retain the event, there might be a situation when a new event object is allocated by the same address as the previous one. In such case the events would be erroneously considered equal.