Enable hermetic builds for iOS.

BUG=669094

Review-Url: https://codereview.chromium.org/2546613004
Cr-Original-Commit-Position: refs/heads/master@{#437269}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 080de20fe53a35ec6b5ce89470261157f9389db3

mac/should_use_hermetic_xcode.py

@@ -4,7 +4,11 @@
 # found in the LICENSE file.
 
 """Prints "1" if Chrome targets should be built with hermetic xcode. Otherwise
-prints "0"."""
+prints "0".
+
+Usage:
+  python should_use_hermetic_xcode.py <target_os>
+"""
 
 import os
 import sys
@@ -15,7 +19,8 @@ def _IsCorpMachine():
 
 
 def main():
-  if os.environ.get('FORCE_MAC_TOOLCHAIN') or _IsCorpMachine():
+  allow_corp = sys.argv[1] == 'mac' and _IsCorpMachine()
+  if os.environ.get('FORCE_MAC_TOOLCHAIN') or allow_corp:
     return "1"
   else:
     return "0"