src/sap.ui.core/src/sap/ui/base/ManagedObjectMetadata.js
function loadOwnDesignTime(oMetadata) {
		if (isPlainObject(oMetadata._oDesignTime) || !oMetadata._oDesignTime) {
			return Promise.resolve(oMetadata._oDesignTime || {});
		}

		return new Promise(function(fnResolve) {
			var sModule;
			if (typeof oMetadata._oDesignTime === "string") {
				//oMetadata._oDesignTime points to resource path to another file, for example: "sap/ui/core/designtime/<control>.designtime"
				sModule = oMetadata._oDesignTime;
			} else {
				sModule = oMetadata.getName().replace(/\./g, "/") + ".designtime";
			}
			preloadDesigntimeLibrary(oMetadata).then(function(oLib) {
				sap.ui.require([sModule], function(mDesignTime) {
					mDesignTime.designtimeModule = sModule;
					oMetadata._oDesignTime = mDesignTime;
					mDesignTime._oLib = oLib;
					fnResolve(mDesignTime);
				});
			});
		});
	}
function loadOwnDesignTime(oMetadata) {
		if (isPlainObject(oMetadata._oDesignTime) || !oMetadata._oDesignTime) {
			return Promise.resolve(oMetadata._oDesignTime || {});
		}

		return new Promise(function(fnResolve) {
			var sModule;
			if (typeof oMetadata._oDesignTime === "string") {
				//oMetadata._oDesignTime points to resource path to another file, for example: "sap/ui/core/designtime/<control>.designtime"
				sModule = oMetadata._oDesignTime;
			} else {
				sModule = oMetadata.getName().replace(/\./g, "/") + ".designtime";
			}
			preloadDesigntimeLibrary(oMetadata).then(function(oLib) {
				sap.ui.require([sModule], function(mDesignTime) {
					mDesignTime.designtimeModule = sModule;
					oMetadata._oDesignTime = mDesignTime;
					mDesignTime._oLib = oLib;
					fnResolve(mDesignTime);
				});
			});
		});
	}
function loadOwnDesignTime ( oMetadata ) { if ( isPlainObject ( oMetadata . _oDesignTime ) || ! oMetadata . _oDesignTime ) { return Promise . resolve ( oMetadata . _oDesignTime || { } ) ; } return new Promise ( function ( fnResolve ) { var sModule ; if ( typeof oMetadata . _oDesignTime === "string" ) { //oMetadata._oDesignTime points to resource path to another file, for example: "sap/ui/core/designtime/<control>.designtime" sModule = oMetadata . _oDesignTime ; } else { sModule = oMetadata . getName ( ) . replace ( / \. / g , "/" ) + ".designtime" ; } preloadDesigntimeLibrary ( oMetadata ) . then ( function ( oLib ) { sap . ui . require ( [ sModule ] , function ( mDesignTime ) { mDesignTime . designtimeModule = sModule ; oMetadata . _oDesignTime = mDesignTime ; mDesignTime . _oLib = oLib ; fnResolve ( mDesignTime ) ; } ) ; } ) ; } ) ; }
Returns a promise that resolves with the own, unmerged designtime data.
If the class is marked as having no designtime data, the promise will resolve with null.

@private
Returns a promise that resolves with the own unmerged designtime data . If the class is marked as having no designtime data the promise will resolve with null .