GitLab

Also moves more common code into InlineEditableItem, and fixes some styling issues with inline-editable lists.

BUG=63817
TEST=Startup pages should be editable in DOMUI prefs. Also, the lead selection in an editable list should show top and bottom borders.

Review URL: http://codereview.chromium.org/6303003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71464 0039d316-1c4b-4281-b951-d872f2087c98