Add breadcrumb for the VM.

runtime/observatory/lib/src/elements/cpu_profile.html

 <link rel="import" href="../../../../packages/polymer/polymer.html">
 <link rel="import" href="code_ref.html">
 <link rel="import" href="function_ref.html">
 <link rel="import" href="nav_bar.html">
 <link rel="import" href="observatory_element.html">
 <link rel="import" href="sliding_checkbox.html">
 <link rel="import" href="view_footer.html">
 
 <polymer-element name="cpu-profile-table" extends="observatory-element">
   <template>
     <link rel="stylesheet" href="css/shared.css">
     <nav-bar>
       <top-nav-menu></top-nav-menu>
+      <vm-nav-menu vm="{{ isolate.vm }}"></vm-nav-menu>
       <isolate-nav-menu isolate="{{ isolate }}"></isolate-nav-menu>
       <nav-menu link="{{ makeLink('/profiler-table', isolate) }}" anchor="cpu profile (table)" last="{{ true }}"></nav-menu>
       <nav-refresh callback="{{ refresh }}"></nav-refresh>
       <nav-refresh callback="{{ clear }}" label="Clear"></nav-refresh>
     </nav-bar>
     <style>
       /* general */
       .well {
         background-color: #ECECEC;
         padding: 0.2em;
@@ skipping 245 matching lines @@
       </div>
     </div>
   </template>
 </polymer-element>
 
 <polymer-element name="cpu-profile" extends="observatory-element">
   <template>
     <link rel="stylesheet" href="css/shared.css">
     <nav-bar>
       <top-nav-menu></top-nav-menu>
+      <vm-nav-menu vm="{{ isolate.vm }}"></vm-nav-menu>
       <isolate-nav-menu isolate="{{ isolate }}"></isolate-nav-menu>
       <nav-menu link="{{ makeLink('/profiler', isolate) }}" anchor="cpu profile" last="{{ true }}"></nav-menu>
       <nav-refresh callback="{{ refresh }}"></nav-refresh>
       <nav-refresh callback="{{ clear }}" label="Clear"></nav-refresh>
     </nav-bar>
     <style>
       .tableWell {
         background-color: #ECECEC;
         padding: 0.2em;
       }
@@ skipping 174 matching lines @@
           <tbody id="treeBody">
           </tbody>
         </table>
       </div>
     </div>
     <view-footer></view-footer>
   </template>
 </polymer-element>
 
 <script type="application/dart" src="cpu_profile.dart"></script>