src/vs/workbench/services/progress/browser/progressIndicator.ts/CompositeScope/registerListeners
class CompositeScope:	registerListeners(): void {
		this._register(this.viewsService.onDidChangeViewVisibility(e => e.visible ? this.onScopeOpened(e.id) : this.onScopeClosed(e.id)));

		this._register(this.viewletService.onDidViewletOpen(viewlet => this.onScopeOpened(viewlet.getId())));
		this._register(this.panelService.onDidPanelOpen(({ panel }) => this.onScopeOpened(panel.getId())));

		this._register(this.viewletService.onDidViewletClose(viewlet => this.onScopeClosed(viewlet.getId())));
		this._register(this.panelService.onDidPanelClose(panel => this.onScopeClosed(panel.getId())));
	}