Automatically repaint when a child view is added or going to be removed.

BUG=333173
TEST=Changing between tabs with translate infobars for different source languages should redraw the infobars.
R=sky@chromium.org

Review URL: https://codereview.chromium.org/138143023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251384 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251384