Editor scrolling:
- Improve TinyMCE resizing when a floated block is at the end of the content.
- Improve setting the padding/margin under the toolbar on loading.
- Add custom event on TinyMCE resizing and use it to adjust the pinning (if needed).
Part props avryl, see #28328.
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git-svn-id: http://core.svn.wordpress.org/trunk@29061 1a063a9b-81f0-0310-95a4-ce76da25c4cd