src/vs/base/browser/fastDomNode.ts/FastDomNode/setFontSize
class FastDomNode:	public setFontSize(_fontSize: number | string): void {
		const fontSize = numberAsPixels(_fontSize);
		if (this._fontSize === fontSize) {
			return;
		}
		this._fontSize = fontSize;
		this.domNode.style.fontSize = this._fontSize;
	}