RFR: 8242597: Remove GenericTaskQueue<>::push_slow

[Kim Barrett]

> On Apr 14, 2020, at 4:32 AM, Ivan Walulya <ivan.walulya at oracle.com> wrote:
> 
> Looks good. 

Thanks.

> 
>> On 14 Apr 2020, at 05:10, Kim Barrett <kim.barrett at oracle.com> wrote:
>> 
>> Please review this change which simplifies GenericTaskQueue::push() by
>> removing some provably unnecessary code.  The case that push_slow was
>> handling, where dirty_size == N-1, cannot occur.  Also added or
>> updated some related comments.
>> 
>> CR:
>> https://bugs.openjdk.java.net/browse/JDK-8242597
>> 
>> Webrev:
>> https://cr.openjdk.java.net/~kbarrett/8242597/open.00/
>> 
>> Testing:
>> mach5 tier1-7