docs: Android design CSS/JS fixes

- Remove new window icon for Developer site link
- Make videos re-load and replay on click to prevent
  failed replay for unseekable videos

Change-Id: I689607d0d53247b0e599612cb7d23a98d6ad24a1

Author: romannurik

docs/html/design/static/default.css

@@ -279,8 +279,7 @@ video.with-shadow {
       background: rgba(0, 0, 0, 0.03); }
   #nav #back-dac-section {
     padding: 10px;
-    border-top: 1px solid #ddd;
-    background: transparent url(open_new_page.png) no-repeat scroll 139px 9px; }
+    border-top: 1px solid #ddd; }
     #nav #back-dac-section a {
       color: #333333;
       font-weight: 500;
@@ -569,4 +568,4 @@ li.no-bullet {
     height: 12px;
     margin-right: 8px; }
   .video-instructions:after {
-    content: 'Click or move mouse over screenshot to replay movie.'; }
+    content: 'Click to replay movie.'; }

docs/html/design/static/default.js

@@ -125,7 +125,8 @@ $(document).ready(function() {
   });
 
   // Set up play-on-hover <video> tags.
-  $('video.play-on-hover').bind('mouseenter click', function(){
+  $('video.play-on-hover').bind('click', function(){
+    $(this).get(0).load(); // in case the video isn't seekable
     $(this).get(0).play();
   });