src/vs/workbench/browser/parts/views/viewsService.ts/ViewsService/getViewProgressIndicator
class ViewsService:	getViewProgressIndicator(viewId: string): IProgressIndicator | undefined {
		const viewContainer = this.viewDescriptorService.getViewContainerByViewId(viewId);
		if (!viewContainer) {
			return undefined;
		}

		const viewPaneContainer = this.viewPaneContainers.get(viewContainer.id);
		if (!viewPaneContainer) {
			return undefined;
		}

		const view = viewPaneContainer.getView(viewId);
		if (!view) {
			return undefined;
		}

		if (viewPaneContainer.isViewMergedWithContainer()) {
			return this.getViewContainerProgressIndicator(viewContainer);
		}

		return view.getProgressIndicator();
	}