Update JVMTI GetThreadState for an unmounted carrier thread

New behaviour was noticed in JTREG GetThreadStateMountedTest.

An unmounted carrier thread is considered implicitly parked,
and all other bits except ALIVE and SUSPENDED are removed from
the bitmask.

Related: #18810

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

Author: babsingh

runtime/jvmti/jvmtiHelpers.cpp

@@ -805,14 +805,15 @@ getThreadState(J9VMThread *currentThread, j9object_t threadObject)
 	jint state = getThreadStateHelper(currentThread, threadObject, vmThread);
 
 #if JAVA_SPEC_VERSION >= 19
-	if (J9_ARE_ANY_BITS_SET(state, JVMTI_THREAD_STATE_RUNNABLE)) {
+	if (J9_ARE_ANY_BITS_SET(state, JVMTI_THREAD_STATE_ALIVE)) {
 		if ((NULL != vmThread->currentContinuation)
 		&& (vmThread->threadObject != vmThread->carrierThreadObject)
 		) {
 			/* If a virtual thread is mounted on a carrier thread, then the carrier thread
-			 * is considered implicitly parked.
+			 * is considered implicitly parked, and all other bits except ALIVE and SUSPENDED
+			 * are removed from the bitmask.
 			 */
-			state &= ~JVMTI_THREAD_STATE_RUNNABLE;
+			state &= (JVMTI_THREAD_STATE_ALIVE | JVMTI_THREAD_STATE_SUSPENDED);
 			state |= JVMTI_THREAD_STATE_WAITING_INDEFINITELY;
 			state |= JVMTI_THREAD_STATE_WAITING;
 		}