src/vs/base/browser/ui/inputbox/inputBox.ts/HistoryInputBox/showPreviousValue
class HistoryInputBox:	public showPreviousValue(): void {
		if (!this.history.has(this.value)) {
			this.addToHistory();
		}

		let previous = this.getPreviousValue();
		if (previous) {
			previous = previous === this.value ? this.getPreviousValue() : previous;
		}

		if (previous) {
			this.value = previous;
			aria.status(this.value);
		}
	}