Artyom Drozdov

Multithreading is always complicated. I mean, there is no way to have a sharable state with easy concurrent access at the one hand, and no problems with it at the...

There actually three places here, that makes me sad: cancelAll, hasSerialRunning and take. If we remove the iteration there, there will be no need to make it lock-free and full...

For hasSerialRunning and take we could use ArrayListMultimap from guava. Or, if you don't wan't to have such dependency, we could implement it by `Map`.

Oh, it is not a problem - we can easely adapt it too.

Android way to achieve this - just to cancel tasks by id without allowing inturruption. And then - just add another one.

Sorry, I'm just forgotten that I've done this PR. So, I'm using my master-branch for own development. If you still interested in PR, I can make it in a separate...

Yep, I've tested it. And I can add more checks to Task/Plugin Specs. If you are feel ok about the idea, I'll prepare separate PR and close this one.