chromite_wrapper: Add support for gclient checkouts.

support/chromite_wrapper

 #!/usr/bin/env python
 # Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Wrapper for chromite tools.
 
 The script is intend to be symlinked to any number of chromite tools, attempts
 to find the path for chromite, and hands off to the right tool via exec if
 possible.
@@ skipping 11 matching lines @@
 import errno
 import os
 import sys
 
 # Due to historical reasons, and the fact depot_tools ToT is used by older
 # factory branches (lacking chromite script cleanups), note we have to
 # fallback to some odd import locations.  This is the only reason for the
 # fallback code- any/all new scripts symlinked to this script *must* exist
 # in chromite/bin/ .
 
-def _FindRoot(path):
-  """Find the root of a repo checkout"""
+def _FindChromite(path):
+  """Find the chromite dir in a repo or gclient checkout."""
   path = os.path.abspath(path)
+  # Depending on the checkout type (whether repo chromeos or gclient chrome)
+  # Chromite lives in a different location.
+  roots = (
+    ('.repo', 'chromite/.git'),
+    ('.gclient', 'src/third_party/chromite/.git'),
+  )
+
   while path != '/':
-    # Look for the chromite repository itself- it's always been at the root
-    # of a repo checkout.
-    if all(os.path.exists(os.path.join(path, x))
-           for x in ['.repo', 'chromite/.git']):
-      return path
+    for root, chromite_git_dir in roots:
+      if all(os.path.exists(os.path.join(path, x))
+             for x in [root, chromite_git_dir]):
+        return os.path.dirname(os.path.join(path, chromite_git_dir))
     path = os.path.dirname(path)
   return None
 
 
 def _MissingErrorOut(target):
   sys.stderr.write(
 """ERROR: Couldn't find the chromite tool %s.
 
 Please change to a directory inside your Chromium OS source tree
 and retry.  If you need to setup a Chromium OS source tree, see
   http://www.chromium.org/chromium-os/developer-guide
 """ % target)
   return 127
 
 
 def main():
-  root = _FindRoot(os.getcwd())
+  chromite_dir = _FindChromite(os.getcwd())
   target = os.path.basename(sys.argv[0])
-  if root is None:
+  if chromite_dir is None:
     return _MissingErrorOut(target)
-  
-  path = os.path.join(root, 'chromite/bin', target)
+
+  path = os.path.join(chromite_dir, 'bin', target)
   try:
     os.execv(path, [path] + sys.argv[1:])
   except EnvironmentError, e:
     if e.errno not in (errno.ENOENT, errno.EPERM):
       raise
 
   # Reaching here means it's either a bad target, or we're working against
   # an old (pre 6be2efcf5bb575b03862113eec097c44d8d7f93e) revision of
   # chromite.  Fallback to trying to import it; this code works at least as
   # far back as branch 0.11.241.B; likely further.
-  
+
   if target == 'cbuildbot':
     target = 'chromite.buildbot.cbuildbot'
   else:
     target = 'chromite.bin.%s' % (target,)
 
   # Adjust the path importation so we can import our our target.
-  sys.path.insert(0, root)
+  sys.path.insert(0, os.path.dirname(chromite_dir))
 
   try:
     module = __import__(target, fromlist=['main'])
   except ImportError:
     return _MissingErrorOut(target)
   return module.main()
 
 if __name__ == '__main__':
   sys.exit(main())