GUACAMOLE-346: Simplify style of seek callback invocation.

guacamole-common-js/src/main/webapp/modules/SessionRecording.js

@@ -384,13 +384,10 @@ Guacamole.SessionRecording = function SessionRecording(tunnel) {
             if (currentFrame !== index)
                 seekToFrame(index, callback);
 
-            else {
-
-                // Notify that the requested seek has completed
+            // Notify that the requested seek has completed
+            else
                 callback();
 
-            }
-
         }, 0);
 
     };