fix(invite): IFrame api when invalid invitees are passed.

modules/API/API.js

         const { name } = request;
 
         switch (name) {
-        case 'invite':
+        case 'invite': // eslint-disable-line no-case-declarations
+            const { invitees } = request;
+
+            if (!Array.isArray(invitees) || invitees.length === 0) {
+                callback({
+                    error: new Error('Unexpected format of invitees')
+                });
+
+                break;
+            }
+
             // The store should be already available because API.init is called
             // on appWillMount action.
             APP.store.dispatch(
-                invite(request.invitees, true))
+                invite(invitees, true))
                 .then(failedInvitees => {
                     let error;
                     let result;

modules/API/external/external_api.js

                 }
             })
         });
-        this.invite(invitees);
+        if (Array.isArray(invitees) && invitees.length > 0) {
+            this.invite(invitees);
+        }
         this._isLargeVideoVisible = true;
         this._numberOfParticipants = 0;
         this._participants = {};
      * @returns {Promise} - Resolves on success and rejects on failure.
      */
     invite(invitees) {
+        if (!Array.isArray(invitees) || invitees.length === 0) {
+            return Promise.reject(new TypeError('Invalid Argument'));
+        }
+
         return this._transport.sendRequest({
             name: 'invite',
             invitees