When passing out the user gesture token, also pass the ref count

This is a follow to to r171900 - the token is now used in a different
event handler and should not longer be held by the page's event handler

BUG=364405

Review URL: https://codereview.chromium.org/246013004

git-svn-id: svn://svn.chromium.org/blink/trunk@172124 bbb929c8-8fbe-4397-9dbb-9b2b20218538