Method isExtensionScriptRequired_

src/service/extensions-impl.js:619–633

* Determine the need to add amp extension script to document. * @param {string} extensionId * @param {string} version * @param {!ExtensionHolderDef} holder * @return {boolean} * @private

(extensionId, version, holder)

   * @private
   */
  isExtensionScriptRequired_(extensionId, version, holder) {
    if (holder.loaded || holder.error) {
      return false;
    }
    if (holder.scriptPresent === undefined) {
      const scriptsInHead = getExtensionScripts(
        this.win,
        extensionId,
        version,
        holder.latest
      );
      holder.scriptPresent = scriptsInHead.length > 0;
    }
    return !holder.scriptPresent;
  }
}

/**