deleteChatMessages(groupId, chatId, messages, callback) {
		return StdLib.Promises.timeoutCallbackPromise(10000, null, callback, true, (resolve, reject) => {
			if (!Array.isArray(messages)) {
				return reject(new Error('The \'messages\' argument must be an array'));
			}

			for (let i = 0; i < messages.length; i++) {
				if (!messages[i] || typeof messages[i] !== 'object' || (!messages[i].server_timestamp && !messages[i].timestamp)) {
					return reject(new Error('The \'messages\' argument is malformed: must be an array of objects with properties {(server_timestamp|timestamp), ordinal}'));
				}
			}

			messages = messages.map((msg) => {
				let out = {};

				msg.ordinal = msg.ordinal || 0;
				if (msg.timestamp && !msg.server_timestamp) {
					msg.server_timestamp = msg.timestamp;
				}

				out.server_timestamp = convertDateToUnix(msg.server_timestamp);

				if (msg.ordinal) {
					out.ordinal = msg.ordinal;
				}

				return out;
			});

			this.user._sendUnified('ChatRoom.DeleteChatMessages#1', {
				chat_group_id: groupId,
				chat_id: chatId,
				messages
			}, (body, hdr) => {
				let err = Helpers.eresultError(hdr.proto);
				if (err) {
					return reject(err);
				}

				resolve();
			});
		});
	}
Delete one or more messages from a chat channel.
@param {int|string} groupId
@param {int|string} chatId
@param {{server_timestamp, ordinal}[]} messages
@param {function} [callback]
@returns {Promise}