Acquire interruptLock for interruptImpl and isInterruptedImpl

interruptImpl and isInterruptedImpl use the eetop/threadRef value.
Acquiring interruptLock assures that the eetop/threadRef value won't
change during interruptImpl and isInterruptedImpl. This will prevent
crashes which happen when a stale eetop/threadRef value is used to
invoke OMR thread library functions.

Related: eclipse-openj9/openj9#19544
Related: eclipse-openj9/openj9#19598

Signed-off-by: Babneet Singh <sbabneet@ca.ibm.com>

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

@@ -1774,7 +1774,9 @@ public static boolean interrupted() {
  public boolean isInterrupted() {
  // use fully qualified name to avoid ambiguous class error
  if (com.ibm.oti.vm.VM.isJVMInSingleThreadedMode()) {
- return isInterruptedImpl();
+ synchronized (interruptLock) {
+ return isInterruptedImpl();
+ }
  }
  return interrupted;
  }
@@ -3031,7 +3033,9 @@ private void setPriority0(int newPriority) {
  }
 
  private void interrupt0() {
- interruptImpl();
+ synchronized (interruptLock) {
+ interruptImpl();
+ }
  }
 
  private static void clearInterruptEvent() {