Fix wrong order of execution in compound assignment nodes (located by Kevin).

tests/language/compound_assignment_operator_test.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // Tests that lhs of a compound assignement is executed only once.
 
 
 class Indexed {
   Indexed() : _f = new List(10), count = 0 {
     _f[0] = 100;
     _f[1] = 200;
   }
   operator [](i) {
     count++;
     return _f;
   }
   var count;
   var _f;
 }
 
+var result;
+
+class A {
+  get field() { result.add(1); return 1; }
+  set field(value) {}
+}
+
+
 class CompoundAssignmentOperatorTest {
 
   static void testIndexed() {
     Indexed indexed = new Indexed();
     Expect.equals(0, indexed.count);
     var tmp = indexed[0];
     Expect.equals(1, indexed.count);
     Expect.equals(100, indexed[4][0]);
     Expect.equals(2, indexed.count);
     Expect.equals(100, indexed[4][0]++);
     Expect.equals(3, indexed.count);
     Expect.equals(101, indexed[4][0]);
     Expect.equals(4, indexed.count);
     indexed[4][0] += 10;
     Expect.equals(5, indexed.count);
     Expect.equals(111, indexed[4][0]);
     var i = 0;
     indexed[3][i++] += 1;
     Expect.equals(1, i);
   }
+  
+  
+  static testIndexedMore() {
+     result = [];
+     array() { result.add(0); return [0]; }
+     index() { result.add(1); return 0; }
+     middle() { result.add(2); }
+     sequence(a, b, c) { result.add(3); }
+
+     sequence(array()[index()] += 1, middle(), array()[index()] += 1);
+     Expect.listEquals([0, 1, 2, 0, 1, 3], result);
+  }
+  
+  static testIndexedMoreMore() {
+    result = [];
+    middle() { result.add(2); }
+    obj() { result.add(0); return new A(); }
+    sequence(a, b, c) { result.add(3); }
+
+    sequence(obj().field += 1, middle(), obj().field += 1);
+    Expect.listEquals([0, 1, 2, 0, 1, 3], result);
+  }
+  
 
   static void testMain() {
     testIndexed();
+    testIndexedMore();
+    testIndexedMoreMore();
   }
 }
+
 main() {
   CompoundAssignmentOperatorTest.testMain();
 }