TinyMCE: don't hide the image toolbar when the iframe window fires onresize. There is a bug in several browsers that triggers onresize when a tooltip is shown, only in RTL mode. Also use better variable name. Fixes #30147.
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git-svn-id: http://core.svn.wordpress.org/trunk@30549 1a063a9b-81f0-0310-95a4-ce76da25c4cd