src/vs/workbench/services/extensions/common/extensionHostManager.ts/LazyStartExtensionHostManager/activateByEvent
class LazyStartExtensionHostManager:	public async activateByEvent(activationEvent: string, activationKind: ActivationKind): Promise<void> {
		if (activationKind === ActivationKind.Immediate) {
			// this is an immediate request, so we cannot wait for start to be called
			if (this._actual) {
				return this._actual.activateByEvent(activationEvent, activationKind);
			}
			return;
		}
		await this._startCalled.wait();
		if (this._actual) {
			return this._actual.activateByEvent(activationEvent, activationKind);
		}
	}