Always reset touch action at the beginning of a new gesture sequence

The InputRouter now tells the TouchActionFilter when a new gesture
sequence is starting, and the allowed_touch_action_ is set to auto.

BUG=344536
TESTS=TouchActionFilterTest.TouchActionResetsOnNewTouchActionSequence

Review URL: https://codereview.chromium.org/171283002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253841 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253841