Create a common directory of widgets and css.

appengine/chromium_rietveld/new_static/components/cr-patch-file-messages.html

 <!-- Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file. -->
 
 <link rel="import" href="cr-patch-file-message.html">
 
 <polymer-element name="cr-patch-file-messages" attributes="beforeMessages afterMessages file">
     <template>
-        <link rel="stylesheet" href="common.css">
+        <link rel="stylesheet" href="../common/common.css">
         <style>
             :host {
                 display: block;
             }
 
             cr-patch-file-message {
                 background-color: #ffd;
                 border-bottom: 1px solid #dcdcdc;
             }
 
@@ skipping 99 matching lines @@
                 this.file.removeMessage(message);
                 this.beforeMessages.remove(message);
                 this.afterMessages.remove(message);
                 // TODO(esprehn): Is there a better way than removing yourself?
                 if (!this.beforeMessages.length && !this.afterMessages.length)
                     this.remove();
             },
         });
     </script>
 </polymer-element>