* Add focus to arrows on Next/Previous in the grid's modal on left/right keypress, and add the necessary CSS for `:focus`
* When in a disabled input in the grid modal, allow the left/right keys to work
* Make the image editor return a `$.Deferred` so that there isn't a race condition with UI loading.
* Assign focus when the edit image mode is rendered so that the modal can be closed on Esc press
Props wonderboymusic, adamsilverstein (for the initial patch).
See #23560.
git-svn-id: https://develop.svn.wordpress.org/trunk@29560 602fd350-edb4-49c9-b593-d223f7449a82
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