src/vs/workbench/browser/parts/views/viewsService.ts/ViewsService/getOrCreateActiveViewContextKey
class ViewsService:	private getOrCreateActiveViewContextKey(view: IView): IContextKey<boolean> {
		const visibleContextKeyId = getVisbileViewContextKey(view.id);
		let contextKey = this.visibleViewContextKeys.get(visibleContextKeyId);
		if (!contextKey) {
			contextKey = new RawContextKey(visibleContextKeyId, false).bindTo(this.contextKeyService);
			this.visibleViewContextKeys.set(visibleContextKeyId, contextKey);
		}
		return contextKey;
	}