8328879: G1: Some gtests modify global state crashing the JVM during GC after JDK-8289822

Reviewed-by: iwalulya, kbarrett

Author: Thomas Schatzl

test/hotspot/gtest/gc/g1/test_freeRegionList.cpp

@@ -34,7 +34,7 @@
 #include "unittest.hpp"
 
 // @requires UseG1GC
-TEST_VM(FreeRegionList, length) {
+TEST_OTHER_VM(FreeRegionList, length) {
   if (!UseG1GC) {
     return;
   }

test/hotspot/gtest/gc/g1/test_heapRegion.cpp

@@ -122,7 +122,7 @@ void VM_HeapRegionApplyToMarkedObjectsTest::doit() {
   region->set_top(old_top);
 }
 
-TEST_VM(HeapRegion, apply_to_marked_object) {
+TEST_OTHER_VM(HeapRegion, apply_to_marked_object) {
   if (!UseG1GC) {
     return;
   }