Only show controls for presenter.

static/partials/pdfviewer.html

@@ -3,7 +3,7 @@
         <canvas class="pdfviewercanvas" ng-hide="canvasIndex"></canvas>
         <canvas class="pdfviewercanvas" ng-show="canvasIndex"></canvas>
     </div>
-	<div class="overlaybar form-horizontal" ng-class="{notvisible: hideControlsBar}">
+	<div class="overlaybar form-horizontal" ng-class="{notvisible: hideControlsBar}" ng-show="isPresenter">
 		<a class="overlaybar-button" ng-model="hideControlsBar" btn-checkbox btn-checkbox btn-checkbox-true="0" btn-checkbox-false="1" title="{{_('PDF controls')}}"><i class="fa fa-cogs"></i></a>
 		<form class="overlaybar-content form-group">
             <a class="btn" ng-click="prevPage()" ng-show="currentPageNumber &gt; 1" title="{{_('Prev')}}"><i class="fa fa-backward"></i></a>