Avoid removing new-instance instruction twice.
Includes a fail-before/pass-after regression test.

Rationale:
In some corner cases, one new instance reached more than one
java.lang.String.<init> method call. As a result, the new
instance instruction appeared multiple times in the vector
uninitialized_strings_. A second removal crashes the compiler.
This change list avoid the crash by simply skipping instructions
that are already removed.

BUG=27847265

Change-Id: I7f8a4f84ea3c184e1529ec3e90bd6749c83c445b
diff --git a/test/591-new-instance-string/src/Main.java b/test/591-new-instance-string/src/Main.java
new file mode 100644
index 0000000..bd59b95
--- /dev/null
+++ b/test/591-new-instance-string/src/Main.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+import java.lang.reflect.*;
+
+public class Main {
+
+  public static void main(String args[]) throws Throwable {
+    Class<?> c = Class.forName("NewInstance");
+    Method m = c.getMethod("multipleInit", int.class);
+    m.invoke(null, 0);
+    m.invoke(null, 1);
+    System.out.println("passed");
+  }
+}