http://bugs.webkit.org/show_bug.cgi?id=3387
        Redundant keydown, keypress, keyup events sent for arrow keys

        Added another layer of ugly hacks around AppKit event dispatching.

        1. For arrow keys, keyDown: is invoked after performKeyEquivalent:, so had to store
        _private->keyDownEvent in both methods, and make it persist after leaving them.

        2. For Esc, AppKit calls performKeyEquivalent: with a fake event of some kind,
        use [NSApp currentEvent] to check for this to prevent it from being passed to  WebCore.

        Test: manual-tests/arrow-key-events.html

        * WebView/WebHTMLView.m:
        (-[NSMutableDictionary dealloc]):
        (-[NSArray keyDown:]):
        (-[NSArray keyUp:]):
        (-[NSArray performKeyEquivalent:]):
        * WebView/WebHTMLViewInternal.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@17760 268f45cc-cd09-0410-ab3c-d52691b4dbfc