Add synchronization when setting interrupted field in Thread::interrupt

This patch fixes eclipse-openj9/openj9#19304.
Setting the interrupted field to true and calling interrupt0 in
Thread::interrupt used to be synchronized via interruptLock. An OpenJDK
change removed this synchronization which caused a data race on the
interrupted field with ReentrantLockTest leading to intermittent
test failures.

This patch adds the synchronized block around setting interrupted and
calling interrupt0 and eliminates the data race with ReentrantLockTest.

Issues: eclipse-openj9/openj9#19304
Signed-off-by: Nathan Henderson <[email protected]>

src/java.base/share/classes/java/lang/Thread.java

@@ -1724,8 +1724,10 @@ public void interrupt() {
         }
 
         // Setting the interrupt status must be done before reading nioBlocker.
-        interrupted = true;
-        interrupt0();  // inform VM of interrupt
+        synchronized (interruptLock) {
+            interrupted = true;
+            interrupt0();  // inform VM of interrupt
+        }
 
         // thread may be blocked in an I/O operation
         if (this != Thread.currentThread()) {