add studio survey button to header.

adds JS to save in local storage whether the user already clicked the
survey. The button appears only if they have not clicked it yet.

Change-Id: Ifc5a100a8bb8505c47d95c7cfb5aaa8cdbfdc8bd
(cherry picked from commit f887aec708)

tools/droiddoc/templates-sdk/components/masthead.cs

@@ -86,7 +86,13 @@
           <span class="dac-sprite dac-google-play"></span>
           <span class="dac-visible-desktop-inline">Developer</span>
           Console
-        </a><?cs /if ?>
+        </a>
+        <a class="dac-header-console-btn" id="studio-survey-button"
+          href="http://goo.gl/forms/dOQUuzwBsX"
+          onclick="onClickStudioSurvey()"
+          target="_blank" style="background:#FFE0B2;display:none"
+        >Take a 1 min survey</a>
+        <?cs /if ?>
 
       </div><!-- end header-wrap.wrap -->
     </div><!-- end header -->