Bring back initPolymer, allow boot.js only if using "polymer_experimental.html".

pkg/polymer/e2e_test/canonicalization/test/deploy1_test.dart

Index: pkg/polymer/e2e_test/canonicalization/test/deploy1_test.dart
diff --git a/tests/compiler/dart2js/path with spaces/library space/part space/part space.dart b/pkg/polymer/e2e_test/canonicalization/test/deploy1_test.dart
similarity index 74%
copy from tests/compiler/dart2js/path with spaces/library space/part space/part space.dart
copy to pkg/polymer/e2e_test/canonicalization/test/deploy1_test.dart
index 58aff0fb6e8a8e53197e400cf859718ce5e65606..f67247a152b9a9c304aab880af2e298be885160e 100644
--- a/tests/compiler/dart2js/path with spaces/library space/part space/part space.dart	
+++ b/pkg/polymer/e2e_test/canonicalization/test/deploy1_test.dart
@@ -2,6 +2,5 @@
 // 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.
 
-part of spaces;
-
-bar() => 499;
+library canonicalization.test.deploy1_test;
+export 'deploy_common.dart';