update polymer related info to 0.8.7

src/site/docs/tutorials/indexeddb/index.markdown

 ---
 layout: default
 title: "Use IndexedDB"
 description: "Use IndexedDB for persistence and offline capability for your app."
 has-permalinks: true
 tutorial:
   id: indexeddb
 next: 
 next-title: "Home"
 prev: forms/
@@ skipping 112 matching lines @@
 Use the **Clear** button to delete all the milestones.
 
 <iframe class="running-app-frame"
         style="height:400px;width:600px;"
         src="examples/count_down/out/web/count_down.html">
 </iframe>
 
 <aside class="alert">
 <strong>Version Note:</strong> The count_down app
 is compatible with
-<a href="https://pub.dartlang.org/packages/polymer#versions">polymer.dart 0.8.1</a>.
+<a href="https://pub.dartlang.org/packages/polymer#versions">polymer.dart 0.8.7</a>.
 </aside>
 
 ###Using developer tools to look at the database
 
 You can use the browser's developer tools
 to explore the IndexedDB databases used by your apps.
 In Chrome, select **View&nbsp;>&nbsp;Developer&nbsp;>&nbsp;Developer Tools**,
 then choose **Resources** from the tabs along the top of the window.
 The following diagram shows the database
 for the count_down app with two milestones.
@@ skipping 568 matching lines @@
 
 ###What next?
 
 You've completed the tutorials!
 Check out the Dart
 [code samples](/samples/) and [articles](/articles/).
 
 {% endcapture %}
 
 {% include tutorial.html %}