Revert^4 "Allow structural redefinition on non-final classes."

This reverts commit 664999a12d6fc8a8ef5c0519b12ec1e8a51bb085.

Fixed issues with GC and quickened instructions in parent CLs.

Reason for revert: Fixed issues with GC CHECK fail and device SEGVs.

Test: ./test.py --host
Test: ./test.py --target
Bug: 134162467
Bug: 144168550
Change-Id: Ibacddaf45beb72184f97d53d5d048bd442578658
diff --git a/test/2001-virtual-structural-multithread/src/Main.java b/test/2001-virtual-structural-multithread/src/Main.java
new file mode 100644
index 0000000..89b8557
--- /dev/null
+++ b/test/2001-virtual-structural-multithread/src/Main.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class Main {
+  public static void main(String[] args) throws Exception {
+    System.out.println("FAIL: Test is only for art!");
+  }
+}