message: Remove usage of "use_ios_simulator".
  This GN variable has been removed by
  in favour of directly using "target_environment".
  Cr-Commit-Position: refs/heads/master@{#32448}
diff: @@ -1097,7 +1097,7 @@ if (is_ios || is_mac) {
  # TODO(peterhanspers): Reenable these tests on simulator.
  # See bugs.webrtc.org/7812
  - if (!use_ios_simulator) {
  + if (target_environment != "simulator") {
  sources += [
  "objc/unittests/RTCAudioDeviceModule_xctest.mm",
  "objc/unittests/RTCAudioDevice_xctest.mm",
  