Fix for #1223 (pdf-reader isn't working on chrome, IE, Edge)

cps/static/js/libs/viewer.js

@@ -4372,7 +4372,7 @@ var defaultOptions = {
     kind: OptionKind.WORKER
   },
   workerSrc: {
-    value: '../../../static/js/libs/pdf.worker.js',
+    value: '../build/pdf.worker.js',
     kind: OptionKind.WORKER
   }
 };

cps/templates/readpdf.html

@@ -35,18 +35,18 @@ See https://github.com/adobe-type-tools/cmap-resources
 
 	  <!-- This snippet is used in production (included from viewer.html) -->
 	  <link rel="resource" type="application/l10n" href="{{ url_for('static', filename='locale/locale.properties') }}">
+	  <script src="{{ url_for('static', filename='js/libs/pdf.js') }}"></script>
+
     <script type="text/javascript">
-    window.addEventListener('load', function() {
+    window.addEventListener('webviewerloaded', function() {
         PDFViewerApplicationOptions.set('sidebarViewOnLoad', 0);
         PDFViewerApplicationOptions.set('imageResourcesPath', "{{ url_for('static', filename='css/images/') }}");
         PDFViewerApplicationOptions.set('workerSrc', "{{ url_for('static', filename='js/libs/pdf.worker.js') }}");
         PDFViewerApplicationOptions.set('defaultUrl',"{{ url_for('web.serve_book', book_id=pdffile, book_format='pdf') }}")
     });
     </script>
-    <script src="{{ url_for('static', filename='js/libs/pdf.js') }}"></script>
-    <script src="{{ url_for('static', filename='js/libs/viewer.js') }}"></script>
-
 
+    <script src="{{ url_for('static', filename='js/libs/viewer.js') }}"></script>
 
   </head>