Break long words in Quick Draft content to prevent ugly overflow, as was...

Break long words in Quick Draft content to prevent ugly overflow, as was previously done. props aubreypwd, SergeyBiryukov. see #26658 for trunk.

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git-svn-id: https://core.svn.wordpress.org/trunk@26809 1a063a9b-81f0-0310-95a4-ce76da25c4cd