Cancelling a job that has already started will still call onCancel

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This doesn't really cause me any problems, as I don't use the cancelling, 
I just add this in case anyone is interested.

If a thread starts to execute a job, but before it finishes, the main 
thread cancels the job, then the job will still continue executing, but 
the thread will call job_onCancel instead of job_onFinish. 

I would have expected that the point of no return is when the thread code 
executer checks for mCancelled, and if it is not cancelled at this point 
it would complete and signal back to the main thread that it should call 
job_onFinish, so the main thread shouldn't check on mCancelled.

Original issue reported on code.google.com by Shanni...@gmail.com on 14 Mar 2009 at 3:48