Alter hooks to call into depot_tools lib....

git_cl_hooks.py

-#!/usr/bin/python
 # Copyright (c) 2009 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 os
 import re
 import subprocess
 import sys
 
-# Find depot_tools in PATH, append it to sys.path so we can import.
-paths = os.environ.get("PATH")
-for path in paths.split(':'):
-  if not path.endswith("depot_tools"):
-    continue
-  sys.path.append(path)
-  break
-
+# Imported from depot_tools.
 import gclient_scm
 import presubmit_support
 
 def Backquote(cmd, cwd=None):
   """Like running `cmd` in a shell script."""
   return subprocess.Popen(cmd,
                           cwd=cwd,
                           stdout=subprocess.PIPE).communicate()[0].strip()
 
 
@@ skipping 14 matching lines @@
       raise Exception("Could not parse log message: %s" % log)
     name = m.group(1)
     description = m.group(2)
     files = gclient_scm.CaptureGitStatus([root], upstream_branch)
     issue = Backquote(['git', 'cl', 'status', '--field=id'])
     patchset = None
     self.change = presubmit_support.GitChange(name, description, root, files,
                                               issue, patchset)
 
 
-# Ensure we were called with the necessary number of arguments.
-program_name = os.path.basename(sys.argv[0])
-if len(sys.argv) < 2:
-  raise Exception("usage: %s [upstream branch]" % program_name)
+def RunHooks(hook_name, upstream_branch):
+  commit = (hook_name == 'pre-cl-dcommit')
 
-# Get arguments from how we were called.
-commit = (program_name == 'pre-cl-dcommit')
-upstream_branch = sys.argv[1]
+  # Create our options based on the command-line args and the current checkout.
+  options = ChangeOptions(commit=commit, upstream_branch=upstream_branch)
 
-# Create our options based on the command-line args and the current checkout.
-options = ChangeOptions(commit=commit, upstream_branch=upstream_branch)
-
-# Run the presubmit checks.
-if presubmit_support.DoPresubmitChecks(options.change,
-                                       options.commit,
-                                       options.verbose,
-                                       sys.stdout,
-                                       sys.stdin,
-                                       options.default_presubmit,
-                                       options.may_prompt):
-  sys.exit(0)
-else:
-  sys.exit(1)
+  # Run the presubmit checks.
+  if presubmit_support.DoPresubmitChecks(options.change,
+                                         options.commit,
+                                         options.verbose,
+                                         sys.stdout,
+                                         sys.stdin,
+                                         options.default_presubmit,
+                                         options.may_prompt):
+    sys.exit(0)
+  else:
+    sys.exit(1)