Remove wrong handling of cascade calls in ContainerTracerVisitor. Its super class InferrerVisitor h…

tests/language/cascade2_test.dart

+// Copyright (c) 2013, 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.
+
+// Regression test for dart2js that used to hit an assertion in the
+// container tracer visitor in the presence of cascaded calls.
+
+import "package:expect/expect.dart";
+
+class A {
+  var foo;
+
+  add(list) {
+    foo = list;
+    list.add(2.5);
+    return this;
+  }
+
+  call(arg) => arg;
+}
+
+main() {
+  var foo = [42, 0];
+  var a = new A();
+  var bar = a..add(foo)('WHAT');
+  a..foo[0] = new Object();
+  Expect.throws(() => foo[0] + 2, (e) => e is NoSuchMethodError);
+}