Fix safesync_url handling for git.

scm.py

 # Copyright (c) 2012 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.
 
 """SCM-specific utility classes."""
 
 import cStringIO
 import glob
 import logging
 import os
@@ skipping 384 matching lines @@
     """Parses git-svn output for the first sha1."""
     match = re.search(r'[0-9a-fA-F]{40}', output)
     return match.group(0) if match else None
 
   @staticmethod
   def GetSha1ForSvnRev(cwd, rev):
     """Returns a corresponding git sha1 for a SVN revision."""
     if not GIT.IsGitSvn(cwd=cwd):
       return None
     try:
-      output = GIT.Capture(['svn', 'find-rev', 'r' + str(rev)], cwd=cwd)
-      return GIT.ParseGitSvnSha1(output)
+      git_svn_rev = GIT.Capture(
+          ['svn', 'find-rev', 'r' + str(rev)], cwd=cwd).rstrip()
+      if not git_svn_rev:
+        return None
+      output = GIT.Capture(
+          ['rev-list', '--ancestry-path', '--reverse',
+          '--grep', 'SVN changes up to revision [0-9]*',
+          '%s..refs/remotes/origin/master' % git_svn_rev], cwd=cwd)
+      if not output:
+        return None
+      sha1 = output.splitlines()[0]
+      if not sha1:
+        return None
+      output = GIT.Capture(['rev-list', '-n', '1', '%s^1' % sha1], cwd=cwd)
+      if git_svn_rev != output.rstrip():
+        raise gclient_utils.Error(sha1)
+      return sha1
     except subprocess2.CalledProcessError:
       return None
 
   @staticmethod
   def IsValidRevision(cwd, rev):
     """Verifies the revision is a proper git revision."""
     # 'git rev-parse foo' where foo is *any* 40 character hex string will return
     # the string and return code 0. So strip one character to force 'git
     # rev-parse' to do a hash table look-up and returns 128 if the hash is not
     # present.
@@ skipping 651 matching lines @@
         # revert, like for properties.
         if not os.path.isdir(cwd):
           # '.' was deleted. It's not worth continuing.
           return
         try:
           SVN.Capture(['revert', file_status[1]], cwd=cwd)
         except subprocess2.CalledProcessError:
           if not os.path.exists(file_path):
             continue
           raise