function useUserAgentDataPlatform(ignoreClientHintsFlag = false) {
  if (util.ASSUME_CLIENT_HINTS_SUPPORT) return true;
  // High-entropy API surfaces should not be gated behind the useClientHints
  // check (as in production it is gated behind a define).
  if (!ignoreClientHintsFlag && !useClientHints()) return false;
  const userAgentData = util.getUserAgentData();
  return !!userAgentData && !!userAgentData.platform;
}
@param {boolean=} ignoreClientHintsFlag Iff truthy, the `useClientHints`
    function will not be called when evaluating if User-Agent Client Hints
    Brand data can be used. For existing labs.userAgent API surfaces with
    widespread use, this should be a falsy value so that usage of the Client
    Hints APIs can be gated behind flags / experiment rollouts.
@return {boolean} Whether to use navigator.userAgentData to determine
the current platform.
userAgentData.platform was enabled by default in Chrome 93:
https://www.chromestatus.com/feature/5733498725859328
TODO(user): Skip this check with FEATURESET_YEAR once userAgentData is
present in all major browsers (may not be until 2024).
See https://caniuse.com/mdn-api_navigator_useragentdata.