Add Hypothes.is tweaks back

Author: BigBlueHat

viewer/web/viewer.html

@@ -413,6 +413,8 @@
   </div>
 </div>
 
+  <script src="//hypothes.is/embed.js"></script>
+
   </body>
 </html>
 

viewer/web/viewer.js

@@ -5945,6 +5945,12 @@ var PDFViewerApplication = {
 
   setTitleUsingUrl: function pdfViewSetTitleUsingUrl(url) {
     this.url = url;
+
+    var rel_canonical = document.createElement('link');
+    rel_canonical.href = url;
+    rel_canonical.rel = "canonical";
+    document.head.appendChild(rel_canonical);
+
     try {
       this.setTitle(decodeURIComponent(getFileName(url)) || url);
     } catch (e) {