Cancel DataDetectors menu earlier if we know it can't be presented

Cancel DataDetectors menu earlier if we know it can't be presented
https://bugs.webkit.org/show_bug.cgi?id=138922
<rdar://problem/18950441>

Reviewed by Beth Dakin.

* UIProcess/mac/WKActionMenuController.mm:
(-[WKActionMenuController willOpenMenu:withEvent:]):
If we end up with a menu with no items, don't change selection or anything.

(-[WKActionMenuController menuNeedsUpdate:]):
Move our call to shouldUseActionsWithContext earlier, to menuNeedsUpdate,
and use a bigger hammer (removeAllItems).

* WebView/WebActionMenuController.mm:
(-[WebActionMenuController prepareForMenu:withEvent:]):
Move our call to shouldUseActionsWithContext earlier, to menuNeedsUpdate,
and use a bigger hammer (removeAllItems).

(-[WebActionMenuController willOpenMenu:withEvent:]):
If we end up with a menu with no items, don't change selection or anything.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@176415 268f45cc-cd09-0410-ab3c-d52691b4dbfc