function restoreMetadata() {
						self._metadata = oMetadataBackup;
						assignRUCounters(self);
					}
Retrieves all items.
@param {boolean} bDeserialize  whether to deserialize the content or not
@returns {Promise} a promise that would be resolved in case of successful operation or rejected with
value of the error message if the operation fails. When resolved the Promise will return the array of all
entries in the following format: <code>{key: &lt;myKey>, value: &lt;myValue>}</code>
@private