Re-enable WebNotifications test for linux aura.

This test is now passing, though with console warnings about IsFullScreenMode
not implemented yet for linux and a RENDER WARNING (already noted in
http://crbug.com/333003).

BUG=163931

Review URL: https://codereview.chromium.org/164333010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252046 0039d316-1c4b-4281-b951-d872f2087c98
Re-enable ManyPopupNotifications test for linux aura.

The test passes now, but with the IsFullScreenMode implementation warning (harmless to
this test).

BUG=163931

Review URL: https://codereview.chromium.org/167773003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252047 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252047