Fuchsia: Allows building the full SDK for host and target.

tools/patch_sdk.py

 #!/usr/bin/env python
 # Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 # for details. 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
 import utils
 
 usage = """patch_sdk.py [options]"""
 
 def DisplayBootstrapWarning():
   print """\
 
 
 WARNING: Your system cannot run the checked-in Dart SDK. Using the
 bootstrap Dart executable will make debug builds slow.
 Please see the Wiki for instructions on replacing the checked-in Dart SDK.
 
 https://github.com/dart-lang/sdk/wiki/The-checked-in-SDK-in-tools
 
 """
 
 def BuildArguments():
   result = argparse.ArgumentParser(usage=usage)
-  result.add_argument("--dart-executable", help="dart executable", default=None)
+  result.add_argument("-q", "--quiet",
+                      help="emit no output",
+                      default=False,
+                      action="store_true")
+  result.add_argument("--dart-executable",
+                      help="dart executable",
+                      default=None)
   return result
 
 def main():
   # Parse the options.
   parser = BuildArguments()
   (options, args) = parser.parse_known_args()
   if utils.CheckedInSdkCheckExecutable():
     options.dart_executable = utils.CheckedInSdkExecutable()
   elif options.dart_executable is not None:
-    DisplayBootstrapWarning()
+    if not options.quiet:
+      DisplayBootstrapWarning()
     options.dart_executable = os.path.abspath(options.dart_executable)
   else:
     print >> sys.stderr, 'ERROR: cannot locate dart executable'
     return -1
   dart_file = os.path.join(os.path.dirname(__file__), 'patch_sdk.dart')
   subprocess.check_call([options.dart_executable, dart_file] + args)
   return 0
 
 if __name__ == '__main__':
   sys.exit(main())