mouse down fix

AppKit/CPTextView/CPTextView.j

@@ -735,6 +735,8 @@ var kDelegateRespondsTo_textShouldBeginEditing
 
 - (void)mouseDown:(CPEvent)event
 {
+    [_CPNativeInputManager cancelCurrentInputSessionIfNeeded];
+
     var fraction = [],
         point = [self convertPoint:[event locationInWindow] fromView:nil],
         granularities = [-1, CPSelectByCharacter, CPSelectByWord, CPSelectByParagraph];