Tiled Galleries: revert r757178. The problem was already fixed in r683829, and this last changeset broke things when creating Thumbnail Grid galleries and checking the default Tiled option in Settings - Media.

git-svn-id: https://plugins.svn.wordpress.org/jetpack/trunk@764847 b8457f37-d9ea-0310-8a92-e5e31aec5664