Stop running pub get at gclient sync time and fix build bugs

mojo/public/dart/third_party/async/LICENSE

Index: mojo/public/dart/third_party/async/LICENSE
diff --git a/mojo/public/third_party/jinja2/LICENSE b/mojo/public/dart/third_party/async/LICENSE
similarity index 82%
copy from mojo/public/third_party/jinja2/LICENSE
copy to mojo/public/dart/third_party/async/LICENSE
index 31bf900e58e30fefda848353470298a254b9e47b..de31e1a0a48ad32b577f42e679ce3acb908c2331 100644
--- a/mojo/public/third_party/jinja2/LICENSE
+++ b/mojo/public/dart/third_party/async/LICENSE
@@ -1,22 +1,17 @@
-Copyright (c) 2009 by the Jinja Team, see AUTHORS for more details.
-
-Some rights reserved.
-
+Copyright 2015, the Dart project authors. All rights reserved.
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
 met:
 
     * Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.
-
     * Redistributions in binary form must reproduce the above
       copyright notice, this list of conditions and the following
       disclaimer in the documentation and/or other materials provided
       with the distribution.
-
-    * The names of the contributors may not be used to endorse or
-      promote products derived from this software without specific
-      prior written permission.
+    * Neither the name of Google Inc. nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT