src/vs/workbench/browser/parts/compositeBar.ts/CompositeBar/addComposite
class CompositeBar:	addComposite({ id, name, order, requestedIndex }: { id: string; name: string, order?: number, requestedIndex?: number; }): void {
		// Add to the model
		if (this.model.add(id, name, order, requestedIndex)) {
			this.computeSizes([this.model.findItem(id)]);
			this.updateCompositeSwitcher();
		}
	}