fix backspace problem in chrome/safari

[macjohnny]

see http://yuilibrary.com/trac-archive/tickets/2532834.html for detailed problem description
fixes #2532834, but reopens #2531090, which is imho not as important as the backspace problem, since this makes the editor unusable.

[yahoocla]

CLA is valid!

[prajwalit]

+1
Example to reproduce the problem: http://jsfiddle.net/prajwalit/8VKqD/3/

[okuryu]

Thank you for your contribution. I confirmed resolved the issue.

So can we use if (e.changedType === 'tab') {} instead of switch() {}?

[macjohnny]

@okuryu hi
the switch command could be replaced, i agree with you.
however, i dont understand why the build fails, since only some lines are removed and the error message (null is not a function) doesn't seem like an issue related to this removal.
how can i merge this pull request?

[macjohnny]

@okuryu how about it now?

[okuryu]

Okay, looks good to me. I would like to merge this in the next week.

Travis CI testing passed on Node.js 0.10. Failed on Node.js 0.8, but this is not this PR's fault.

[okuryu]

I have been cherry-picked in 8e1b4ea and 981e911. It will be available in the next release.

For the future contributions, we are working on a few branches normally. Please see Branch Information.

Thanks!