Broke ContentSettingBubbleModelTest.Plugins on Android.

      Revert 180103 - Only permit plug-in loads in the browser if the plug-in isn't blocked or the
user has authorized it with a browser-mediated interaction.

BUG=172573
Review URL: https://codereview.chromium.org/12086077

TBR=cevans@chromium.org
Review URL: https://chromiumcodereview.appspot.com/12114045

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@180110 0039d316-1c4b-4281-b951-d872f2087c98