function _getBindingPath(oElement, mPayload) {
		if (mPayload.path) {
			return mPayload.path;
		}
		var vBinding = oElement.getBindingContext();
		if (vBinding) {
			return vBinding.getPath();
		}
	}
Get binding path either from payload (if available) or the element's binding context.

@param {sap.ui.core.Control} oElement The control instance
@param {object} mPayload The payload parameter attached to the delegate, empty object if no payload was assigned
@returns {string} The binding path
@private