Notify for detecting suspend.

conference.js

                 this.localAudio.dispose();
                 this.localAudio = null;
             }
+
+            APP.API.notifySuspendDetected();
         });
 
         APP.UI.addListener(UIEvents.AUDIO_MUTED, muted => {

doc/api.md

 }
 ```
 
+* **suspendDetected** - event notifications about detecting suspend event in host computer.
+
 You can also add multiple event listeners by using `addEventListeners`.
 This method requires one argument of type Object. The object argument must
 have the names of the events as keys and the listeners of the events as values.

modules/API/API.js

         this._sendEvent({ name: 'video-ready-to-close' });
     }
 
+    /**
+     * Notify external application (if API is enabled) that a suspend event in host computer.
+     *
+     * @returns {void}
+     */
+    notifySuspendDetected() {
+        this._sendEvent({ name: 'suspend-detected' });
+    }
+
     /**
      * Notify external application (if API is enabled) for audio muted status
      * changed.

modules/API/external/external_api.js

     'video-mute-status-changed': 'videoMuteStatusChanged',
     'screen-sharing-status-changed': 'screenSharingStatusChanged',
     'subject-change': 'subjectChange',
+    'suspend-detected': 'suspendDetected',
     'tile-view-changed': 'tileViewChanged'
 };
 
      * {{
      * on: on //whether screen sharing is on
      * }}
+     * {@code suspendDetected} - receives event notifications about detecting suspend event in host computer.
      * {@code readyToClose} - all hangup operations are completed and Jitsi Meet
      * is ready to be disposed.
      * @returns {void}