Adds RTCUIHelper class which gathers methods specific to WebRTC and UI.

JitsiMeetJS.js

 var JitsiTrackErrors = require("./JitsiTrackErrors");
 var Logger = require("jitsi-meet-logger");
 var RTC = require("./modules/RTC/RTC");
+var RTCUIHelper = require("./modules/RTC/RTCUIHelper");
 var Statistics = require("./modules/statistics/statistics");
 var Resolutions = require("./service/RTC/Resolutions");
 var ScriptUtil = require("./modules/util/ScriptUtil");
      */
     util: {
         ScriptUtil: ScriptUtil,
-    },
+        RTCUIHelper: RTCUIHelper
+    }
 };
 
 //Setups the promise object.

modules/RTC/RTC.js

  */
 RTC.isDesktopSharingEnabled = function () {
     return RTCUtils.isDesktopSharingEnabled();
-}
-
-RTC.prototype.getVideoElementName = function () {
-    return RTCBrowserType.isTemasysPluginUsed() ? 'object' : 'video';
 };
 
 RTC.prototype.dispose = function() {
     var resource = Strophe.getResourceFromJid(jid);
     if(this.remoteStreams[resource] && this.remoteStreams[resource][JitsiTrack.AUDIO])
         this.remoteStreams[resource][JitsiTrack.AUDIO].setAudioLevel(audioLevel);
-}
+};
+
 module.exports = RTC;

modules/RTC/RTCUIHelper.js

+/* global $ */
+var RTCBrowserType = require("./RTCBrowserType");
+
+var RTCUIHelper = {
+
+    /**
+     * Returns the name of 'video' element depending on the browser that we're
+     * currently using.
+     * @returns {string} 'video' or 'object' string name of WebRTC video element
+     */
+    getVideoElementName: function () {
+        return RTCBrowserType.isTemasysPluginUsed() ? 'object' : 'video';
+    },
+
+    /**
+     * Finds video element inside of the given container.
+     * @param containerElement HTML element node instance which is supposed to
+     *        contain the video element.
+     * @returns {HTMLElement} video HTML element instance if found inside of the
+     *          container or undefined otherwise.
+     */
+    findVideoElement: function (containerElement) {
+        var videoElemName = RTCUIHelper.getVideoElementName();
+        if (!RTCBrowserType.isTemasysPluginUsed()) {
+            return $(containerElement).find(videoElemName)[0];
+        } else {
+            var matching = $(containerElement).find(
+                ' ' + videoElemName + '>param[value="video"]');
+            if (matching.length < 2) {
+                return matching.parent()[0];
+            } else {
+                // there are 2 video objects from FF
+                // object with id which ends with '_default'
+                // (like 'remoteVideo_default')
+                // doesn't contain video, so we ignore it
+                for (var i = 0; i < matching.length; i += 1) {
+                    var el = matching[i].parentNode;
+
+                    // check id suffix
+                    if (el.id.substr(-8) !== '_default') {
+                        return el;
+                    }
+                }
+            }
+        }
+        return undefined;
+    }
+};
+
+module.exports = RTCUIHelper;