RFR: 8263204: Add Gradle Wrapper Validation Action

[John Neffenger]

On Mon, 8 Mar 2021 22:13:09 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> Thanks, Kevin. I'll merge the two workflow files.
>> 
>> The test results aren't what I expected:
>> 
>> ![some-checks-were-not-successful](https://user-images.githubusercontent.com/1413266/110386542-424dde00-8015-11eb-9cef-97d2ff2a5d27.png)
>> 
>> I assumed the wrapper validation would fail and prevent the builds from running. Should I try to make the three build steps dependent on the success of the wrapper validation? There might be a way to make the steps sequential and conditional.
>
> If it isn't too hard to make the running of the other three jobs dependent on the wrapper validation job, that would be good, as long as the validation job is fast. The other three still need to run in parallel with each other.
> 
> Alternatively, you could make the wrapper validation a task that is replicated in each of the three jobs.

Okay, this is looking better! The validation took only 23 seconds, and GitHub shows the following results:

![some-checks-were-not-successful-2](https://user-images.githubusercontent.com/1413266/110390566-0b7ac680-801b-11eb-8090-f1548046094e.png)

The screenshot below shows the notification I received by e-mail:

![run-failed-message](https://user-images.githubusercontent.com/1413266/110390602-17ff1f00-801b-11eb-9870-c5f955b4739c.png)

Now we'll see whether the three build jobs still run in parallel when the wrapper validation succeeds. My next commit will restore the Gradle Wrapper JAR file.

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PR: https://git.openjdk.java.net/jfx/pull/419