Revisions: RTL tooltip fixes. Plus a fix for switching to compare-two mode while looking at the first revision.

Also, a meta box avatar RTL alignment fix. props DrewAPicture.

Fixes #24739.

git-svn-id: https://core.svn.wordpress.org/trunk@24698 1a063a9b-81f0-0310-95a4-ce76da25c4cd