[Android] Disable 4 failing accessibility-related content browsertests.

BUG=297230
TBR=dmazzoni@chromium.org

Review URL: https://codereview.chromium.org/130273005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246940 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246940