Merge 128999 - Do touch adjustment on GestureTapDown

Merge 128999 - Do touch adjustment on GestureTapDown
https://bugs.webkit.org/show_bug.cgi?id=96677

Patch by Rick Byers <rbyers@chromium.org>; on 2012-09-19
Reviewed by Antonio Gomes.

Source/WebCore:

Do touch adjustment on GestureTapDown exactly as for GestureTap today.

Test: touchadjustment/touch-links-active.html

* page/EventHandler.cpp:
(WebCore::EventHandler::handleGestureEvent):
(WebCore::EventHandler::adjustGesturePosition):

Tools:

Allow radius to be set for GestureTapDown events.
* DumpRenderTree/chromium/TestRunner/EventSender.cpp:
(EventSender::gestureEvent):

LayoutTests:

Make a few tweaks to the touchadjustment.js infrastructure to make it
simpler and easier to use.  Add a test for touch-adjustment of
GestureTapDown events (based on touch-links-longpress).

* touchadjustment/resources/touchadjustment.js:
(touchPoint.return.left.x.radiusX.top.y.radiusY.width.radiusX.2.height.radiusY.2.get x):
(touchPoint.return.get y):
(touchPoint):
(offsetTouchPoint):
* touchadjustment/touch-links-active-expected.txt: Added.
* touchadjustment/touch-links-active.html: Added.

TBR=commit-queue@webkit.org
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=129422