fix(jqLite): forgive unregistration of a non-registered handler

[pkozlowski-opensource]

I've bumped into a subtle bug when unregisering handlers with jqLite. If you try to unregister a non-existing handler by specifing both its type and a function jqLite's off will fail if there was already a different handler was registered. See the test for more details.

With jQuery this situation is handled correctly, that it, unregistration has no effect.

I was hesitating a bit between fixing it in jqLite or fixing directly the indexOf / arrayRemove (in Angular.js). In any case the test illustrates my real problem, can amend the fix if needed.

[mary-poppins]

Thanks for the PR!

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Thanks again for your help!

[pkozlowski-opensource]

• Contributor signed CLA now or in the past (if you just signed, leave a comment here with your real name) - signed, signed, @mary-poppins got it wrong ;-)
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[petebacondarwin]

Dear @pkozlowski-opensource - please ensure that you have signed the CLA :-P

[IgorMinar]

LGTM

[pkozlowski-opensource]

@IgorMinar OK, great, so I'm going to push the fix to master plus a different one for stable (as we've changed unbind to off and as such we can't merge the same code).

[pkozlowski-opensource]

Landed as ab59cc6 and ac5b905.