Fix unintended box-shadow in the opposite corner of thickbox Close icon.

props ocean90.
fixes #29311.
Built from https://develop.svn.wordpress.org/trunk@29575


git-svn-id: http://core.svn.wordpress.org/trunk@29349 1a063a9b-81f0-0310-95a4-ce76da25c4cd
TinyMCE: update to 4.1.4-20140822. Changes:
- Fixed bug where sometimes the resize rectangles wouldn't properly render on images on WebKit/Blink. https://github.com/tinymce/tinymce/commit/9a2d01cc141f71de33c689e19baf026d20cc67be
- Fixed nodeChanged selection issue where the image selection wouldn't be removed if you clicked right after/before it. https://github.com/tinymce/tinymce/commit/dd729c67e066d346f5a4140fa3b4b94f51a235e8
- Fixed bug in list plugin where delete/backspace would merge empty LI elements in lists incorrectly. https://github.com/tinymce/tinymce/commit/caadfb05dd8b9b8dc7b76525188891d5ab47c5ee
See #29310
Built from https://develop.svn.wordpress.org/trunk@29576


git-svn-id: http://core.svn.wordpress.org/trunk@29350 1a063a9b-81f0-0310-95a4-ce76da25c4cd