Fix some more shorten-64-to-32 warnings:

tools/observatory_tool.py

 #!/usr/bin/env python
 # Copyright (c) 2015, 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.
 """Helper for building and deploying Observatory"""
 
 import argparse
 import os
 import platform
 import shutil
@@ skipping 117 matching lines @@
       executable = [pub_executable]
     elif pub_snapshot is not None:
       executable = [utils.CheckedInSdkExecutable(), pub_snapshot]
     else:
       DisplayBootstrapWarning()
       executable = [dart_executable, '--package-root=' + pkg_root, PUB_PATH]
       # Prevent the bootstrap Dart executable from running in regular
       # development flow.
       # REMOVE THE FOLLOWING LINE TO USE the dart_bootstrap binary.
       # return False
+    print >> sys.stderr, ('Running command "%s"') % (executable + command)
     return subprocess.call(executable + command,
                            stdout=silent_sink if silent else None,
                            stderr=silent_sink if silent else None)
 
 def Deploy(input_dir, output_dir):
   shutil.rmtree(output_dir)
   shutil.copytree(input_dir, output_dir, ignore=IGNORE_PATTERNS)
   index_file = os.path.join(output_dir, 'web', 'index.html')
   os.utime(index_file, None)
   return 0
@@ skipping 53 matching lines @@
   if (options.pub_snapshot != None):
     options.pub_snapshot = os.path.abspath(options.pub_snapshot)
   if len(args) == 1:
     args[0] = os.path.abspath(args[0])
   # Pub must be run from the project's root directory.
   ChangeDirectory(options.directory)
   return ExecuteCommand(options, args)
 
 if __name__ == '__main__':
   sys.exit(main());