Method maybeUpdated_

src/core/context/values.js:525–545

* @param {IContextPropUsed } used * @param {T} value * @private * @template T

(used, value)

   * @template T
   */
  maybeUpdated_(used, value) {
    const {prop, value: oldValue} = used;
    const {key} = prop;
    const usedByKey = this.usedByKey_;
    if (
      oldValue === value ||
      used !== usedByKey?.get(key) ||
      !this.isConnected_()
    ) {
      // Either the value didn't change, or no one needs this value anymore.
      return;
    }

    used.value = value;

    // Notify subscribers.
    const {subscribers} = used;
    for (const handler of subscribers) {
      handler(value);
    }
  }

  /**
   * The used value calculation algorithm.