Method updateStyles

packages/core/test/acceptance/styling_spec.ts:2060–2063

(prop: string, value: string | number | null)

      public s: {[key: string]: any} | null = null;
      updateStyles(prop: string, value: string | number | null) {
        const s = this.s || (this.s = {});
        Object.assign(s, {[prop]: value});
      }

      reset() {
        this.s = null;