src/vs/editor/browser/services/abstractCodeEditorService.ts/DecorationCSSRules/collectCSSText
class DecorationCSSRules:	private collectCSSText(opts: any, properties: string[], cssTextArr: string[]): boolean {
		const lenBefore = cssTextArr.length;
		for (const property of properties) {
			const value = this.resolveValue(opts[property]);
			if (typeof value === 'string') {
				cssTextArr.push(strings.format(_CSS_MAP[property], value));
			}
		}
		return cssTextArr.length !== lenBefore;
	}