RFR: Fix shared tests to run without Shenandoah

[Roman Kennke]

Hi Aleksey,

> On 11/28/18 7:21 PM, Roman Kennke wrote:
>>> Okay, what's up with TestFullGCCount test? Does it not run without Shenandoah built? It should. The
>>> @requires line there only protects from running the test with Shenandoah in explicit-concurrent
>>> mode, right? (While you are at it, you can probably change "vm.gc == "Shenandoah"" to
>>> "vm.gc.Shenandoah")
>>
>> The way it was written was very confusing and it was wrong too. All the
>> @requires together would not select any test at all, except default GC.
> 
> Really? Multiple @requires are AND-ed. The @requires in this test are NOT-ed. So, passing both
> requires are actually very easy, no?

Ah hmm. It is confusing, especially with the triple-negation here:
* @requires !(vm.gc == "Shenandoah" &
!(vm.opt.ExplicitGCInvokesConcurrent == false))

Let's do it like this (like line above):

* @requires !(vm.gc == "Shenandoah" & vm.opt.ExplicitGCInvokesConcurrent
== true)

Ok? I find this still slightly confusing (as does Leonid), but seems ok:

http://cr.openjdk.java.net/~rkennke/fix-shared-tests/webrev.03/

Good now?

Roman