Remove mouse-related hit tests during a GestureTap

LayoutTests/fast/events/touch/gesture/focus-selectionchange-on-tap-expected.txt

+Verifies that a GestureTap triggers focus and selectionchange if and only if mousedown isn't prevented.
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+Tap on input field but consume mousedown
+Sending GestureTapDown
+Sending GestureShowPress
+Sending GestureTap
+Received mouseover on target
+Received mousemove on target
+Received mousedown on target
+Received mouseup on target
+Received click on target
+PASS tapHandled is true
+PASS isFocused(target) is false
+
+Tap on input field without consuming mousedown
+Sending GestureTapDown
+Sending GestureShowPress
+Sending GestureTap
+Received mousemove on target
+Received mousedown on target
+Received mouseup on target
+Received click on target
+PASS tapHandled is false
+Received selectionchange on #document anchor=BODY[2]
+PASS isFocused(target) is true
+
+Tap elsewhere to clear focus
+Sending GestureTapDown
+Sending GestureShowPress
+Sending GestureTap
+Received mouseout on target
+PASS tapHandled is false
+Received selectionchange on #document anchor=#text[0]
+Received selectionchange on #document anchor=#text[0]
+PASS isFocused(target) is false
+
+PASS successfullyParsed is true
+
+TEST COMPLETE
+