ART: Fix order of operations in HBasicBlock::DisconnectAndDelete

The method would remove predecessors before successors. As a result,
instructions used by dead loop phis would see dangling uses, causing
a DCHECK to fail.

Steps were reordered to remove dependencies in post order.

Bug: 27683071
Change-Id: I8e0e976443fb410908321a065276f1340b757c41
diff --git a/test/591-checker-regression-dead-loop/src/Main.java b/test/591-checker-regression-dead-loop/src/Main.java
new file mode 100644
index 0000000..6d9fcf8
--- /dev/null
+++ b/test/591-checker-regression-dead-loop/src/Main.java
@@ -0,0 +1,35 @@
+/*
+ * 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.
+ */
+
+class Main {
+  private static boolean $inline$false() { return false; }
+
+  /// CHECK-START: void Main.main(java.lang.String[]) dead_code_elimination (before)
+  /// CHECK-DAG:     <<Const0:i\d+>> IntConstant 0
+  /// CHECK-DAG:     <<Const1:i\d+>> IntConstant 1
+  /// CHECK-DAG:     <<Phi:i\d+>>    Phi [<<Const0>>,<<Add:i\d+>>] loop:{{B\d+}}
+  /// CHECK-DAG:                     InvokeVirtual [{{l\d+}},<<Phi>>] method_name:java.io.PrintStream.println
+  /// CHECK-DAG:     <<Add>>         Add [<<Phi>>,<<Const1>>]
+
+  public static void main(String[] args) {
+    if ($inline$false()) {
+      int x = 0;
+      while (true) {
+        System.out.println(x++);
+      }
+    }
+  }
+}