aura: Fix a couple of issues related to held touch events.

* The held touch event's location should be in the root-window's coordinate
  (and not in the target's coordinate system).
* When a touch-move event is 'held' instead of being dispatched, do not
  generate any gesture events from it.

BUG=332963
R=sky@chromium.org

Review URL: https://codereview.chromium.org/135483002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244537 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244537
Don't populate URL data in WebDropData when dragging files.

This is considered a potential security issue as well, since it leaks
filesystem paths.

BUG=332579

Review URL: https://codereview.chromium.org/135633002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244538 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244538