RFR: 8291640: java/beans/XMLDecoder/8028054/Task.java should use the 3-arg Class.forName

[Ao Qi]

The issue comes from https://github.com/openjdk/jdk/pull/9677#issuecomment-1200811357. 

If Loom is not supported, two XMLDecoder tests would fail. The issue could be reproduced by zero, for example:


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TEST: java/beans/XMLDecoder/8028054/TestConstructorFinder.java
...
Caused by: java.lang.UnsupportedOperationException: VM does not support continuations
	at java.base/jdk.internal.vm.ContinuationSupport.ensureSupported(ContinuationSupport.java:49)
	at java.base/jdk.internal.vm.Continuation.<clinit>(Continuation.java:52)
	... 9 more
...

--------------------------------------------------
TEST: java/beans/XMLDecoder/8028054/TestMethodFinder.java
...
Caused by: java.lang.UnsupportedOperationException: VM does not support continuations
	at java.base/jdk.internal.vm.ContinuationSupport.ensureSupported(ContinuationSupport.java:49)
	at java.base/jdk.internal.vm.Continuation.<clinit>(Continuation.java:52)
	... 9 more
...
--------------------------------------------------

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Commit messages:
 - 8291640: java/beans/XMLDecoder/8028054/Task.java should use the 3-arg Class.forName

Changes: https://git.openjdk.org/jdk/pull/9704/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9704&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291640
  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/9704.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9704/head:pull/9704

PR: https://git.openjdk.org/jdk/pull/9704