Avoid making new active service overlay highlights while the mouse is down

Avoid making new active service overlay highlights while the mouse is down
https://bugs.webkit.org/show_bug.cgi?id=135872
<rdar://problem/17982341>

Reviewed by Enrica Casucci.

* WebProcess/WebPage/ServicesOverlayController.h:
* WebProcess/WebPage/mac/ServicesOverlayController.mm:
(WebKit::ServicesOverlayController::remainingTimeUntilHighlightShouldBeShown):
(WebKit::ServicesOverlayController::mouseEvent):
If the mouse is pressed or it's been less than 200ms since the mouse went up,
don't allow the highlight to change. We apply the mouse-is-pressed rule to telephone
number highlights as well, unlike the rest of the hysteresis logic.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@172528 268f45cc-cd09-0410-ab3c-d52691b4dbfc