Revert "Fix language tests wrt. warnings."

tests/language/crash_6725_part.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 a crash in dart2js.
-
-part of crash_6725;
-
-class Fisk {
-  it1(x) {
-    // "key" is unresolved and caused a crash in dart2js.
-    // This is the original example the user reported.
-    for (key in x) {
-      print(key);
-    }
-  }
-
-  it2(x) {
-    // "length" is "intercepted" and handled differently from other
-    // names when an instance of list is observed.
-    for (length in x) {
-      print(length);
-    }
-  }
-
-  it3(x) {
-    // We're pretty sure that there's no "fisk" that is "intercepted".
-    for (fisk in x) {
-      print(fisk);
-    }
-  }
-}
-
-class SubFisk extends Fisk {
-  var key;
-  var length;
-  var fisk;
-}
-
-test() {
-  Fisk f = new SubFisk();
-  var m = (x) {
-    for (undeclared in x) {
-      print(undeclared);
-    }
-  };
-  if (new DateTime.now().millisecondsSinceEpoch == 42) {
-    f = null;
-    m = (x) {};
-  }
-
-  f.it1([87, 42]);
-  if (f.key != 42) {
-    throw 'f.key != 42 (${f.key})';
-  }
-
-  f.it2([87, 42]);
-  if (f.length != 42) {
-    throw 'f.length != 42 (${f.length})';
-  }
-
-  f.it3([87, 42]);
-  if (f.fisk != 42) {
-    throw 'f.fisk != 42 (${f.fisk})';
-  }
-
-  try {
-    m([87, 42]);
-    throw 'NoSuchMethodError expected';
-  } on NoSuchMethodError {
-    // Expected.
-  }
-}