src/vs/workbench/services/extensions/common/extensionHostManager.ts/LazyStartExtensionHostManager/deltaExtensions
class LazyStartExtensionHostManager:	public async deltaExtensions(extensionsDelta: IExtensionDescriptionDelta): Promise<void> {
		await this._startCalled.wait();
		if (this._actual) {
			return this._actual.deltaExtensions(extensionsDelta);
		}
		this._lazyStartExtensions!.delta(extensionsDelta);
		if (extensionsDelta.myToAdd.length > 0) {
			const actual = this._createActual(`contains ${extensionsDelta.myToAdd.length} new extension(s) (installed or enabled): ${extensionsDelta.myToAdd.map(extId => extId.value)}`);
			const { toAdd, myToAdd } = this._lazyStartExtensions!.toDelta();
			actual.start(toAdd, myToAdd);
			return;
		}
	}