src/vs/workbench/browser/parts/panel/panelPart.ts/PanelPart/hideComposite
class PanelPart:	private hideComposite(compositeId: string): void {
		this.compositeBar.hideComposite(compositeId);

		const compositeActions = this.compositeActions.get(compositeId);
		if (compositeActions) {
			compositeActions.activityAction.dispose();
			compositeActions.pinnedAction.dispose();
			this.compositeActions.delete(compositeId);
		}
	}