src/vs/workbench/services/history/browser/history.ts/HistoryService/reopenLastClosedEditor
class HistoryService:	reopenLastClosedEditor(): void {

		// Open editor if we have one
		const lastClosedEditor = this.recentlyClosedEditors.pop();
		if (lastClosedEditor) {
			this.doReopenLastClosedEditor(lastClosedEditor);
		}

		// Update context
		this.canReopenClosedEditorContextKey.set(this.recentlyClosedEditors.length > 0);
	}