Add basic implementation of IsModifiableClass

Currently we just flatly disallow some types of modifications that
might be allowed in the future.

Bug: 31684578
Test: mma -j40 test-art-host
Change-Id: Ica76d12276eb11b318da2f642591ea78766f36ad
diff --git a/runtime/openjdkjvmti/OpenjdkJvmTi.cc b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
index 28cfd64..644603b 100644
--- a/runtime/openjdkjvmti/OpenjdkJvmTi.cc
+++ b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
@@ -599,7 +599,7 @@
   static jvmtiError IsModifiableClass(jvmtiEnv* env,
                                       jclass klass,
                                       jboolean* is_modifiable_class_ptr) {
-    return ERR(NOT_IMPLEMENTED);
+    return Redefiner::IsModifiableClass(env, klass, is_modifiable_class_ptr);
   }
 
   static jvmtiError GetClassLoader(jvmtiEnv* env, jclass klass, jobject* classloader_ptr) {