Work around Xcode 9 debug actool message.

build/toolchain/mac/compile_xcassets.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import argparse
 import os
 import subprocess
 import sys
 
 
@@ skipping 44 matching lines @@
   #
   # Ignore any lines in the output matching those (last line is an empty line)
   # and consider that the build failed if the output contains any other lines.
   for line in stdout.splitlines():
     if not line:
       continue
     if line == '/* com.apple.actool.compilation-results */':
       continue
     if line == os.path.abspath(output):
       continue
+    # crbug.com/730054 Xcode 9's beta introduced a CoreUI(DEBUG) message and
+    # IBMessageChannelErrorDomain message that can be ignored.
+    if line.startswith('CoreUI(DEBUG)'):
+      continue
+    if 'Error Domain=IBMessageChannelErrorDomain Code=4' in line:
+      continue
     sys.stderr.write(stdout)
     sys.exit(1)
 
 
 def Main():
   parser = argparse.ArgumentParser(
       description='compile assets catalog for a bundle')
   parser.add_argument(
       '--platform', '-p', required=True,
       choices=('macosx', 'iphoneos', 'iphonesimulator'),
@@ skipping 21 matching lines @@
   CompileXCAssets(
       args.output,
       args.platform,
       args.product_type,
       args.minimum_deployment_target,
       args.inputs)
 
 
 if __name__ == '__main__':
   sys.exit(Main())