function findViewSettingsItemByKey(vItemOrKey, aViewSettingsItems, sErrorMessage) {
		var oItem;

		// convenience, also allow strings
		if (typeof vItemOrKey === "string") {
			// find item with this key
			oItem = getViewSettingsItemByKey(aViewSettingsItems, vItemOrKey);

			if (!oItem && sErrorMessage) {
				Log.error(sErrorMessage);
			}
		} else {
			oItem = vItemOrKey;
		}

		return oItem;
	}
Finds an sap.m.ViewSettingsItem from a list of items by a given key.
If it does not succeed logs an error.

@param {sap.m.ViewSettingsItem|string} vItemOrKey The searched item or its key
@param {sap.m.ViewSettingsItem[]} aViewSettingsItems The list of sap.m.ViewSettingsItem objects to be searched
@param {string} sErrorMessage If an error message is provided, it will be logged when the
item is not found
@returns {sap.m.ViewSettingsItem} The sap.m.ViewSettingsItem found in the list of items
@private