Editor scrolling:
- Add a Screen Option to turn it on/off, and on()/off() methods from JS. Store the user preference.
- Fix delayed calls to resize() in the TinyMCE autoresize plugin.
See #28328.
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git-svn-id: http://core.svn.wordpress.org/trunk@29116 1a063a9b-81f0-0310-95a4-ce76da25c4cd