Make montagereview more robust when the storage area of an event has been deleted. Add the onmouse events using javascript instead of in the html canvas element so that our CSP policy works.

web/skins/classic/views/montagereview.php

@@ -290,7 +290,7 @@ if ( (!$liveMode) and (count($displayMonitors) != 0) ) {
       </div>
 <?php } // end if !live ?>
       <div id="timelinediv">
-        <canvas id="timeline" onmousemove="mmove(event);" ontouchmove="tmove(event);" onmousedown="mdown(event);" onmouseup="mup(event);" onmouseout="mout(event);"></canvas>
+        <canvas id="timeline"></canvas>
         <span id="scrubleft"></span>
         <span id="scrubright"></span>
         <span id="scruboutput"></span>