Enable Device Orientation browser test.

Now that Blink has switched to the new Device Orientation
implementation (see https://codereview.chromium.org/22599005/)
we can re-enable this slightly modified browser test.

BUG=298066
TBR=mvanouwerkerk@chromium.org

Review URL: https://codereview.chromium.org/27169004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228672 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228672