Add back CSS rules for RTL resize handles.

Disable CSSJanus' swapLtrRtlInUrl option, as we currently don't use it otherwise (and it breaks this if left on).

props ocean90.
fixes #26449.

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git-svn-id: http://core.svn.wordpress.org/trunk@26620 1a063a9b-81f0-0310-95a4-ce76da25c4cd