Do not evaluate arguments of an instance send if that instance send is being inlined. The inliner w…

tests/language/inline_argument_test.dart

+// Copyright (c) 2012, 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.
+// Test that when inlining A.foo, we're not evaluating the argument
+// twice.
+
+class A {
+  var field = 0;
+
+  foo(b) {
+    Expect.equals(0, b);
+    Expect.equals(0, b);
+  }
+
+  bar() {
+    foo(field++);
+  }
+}
+
+main() {
+  var a = new A();
+  a.bar();
+  Expect.equals(1, a.field);
+}