[depot_tools] Use git fetch to optimize the properly configured that use git-svn

gclient_scm.py

 # Copyright (c) 2011 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.
 
 """Gclient-specific SCM-specific operations."""
 
 import logging
 import os
 import posixpath
 import re
@@ skipping 482 matching lines @@
     # [0-9]{1,6} for now to avoid making a network request.
     if rev.isdigit() and len(rev) < 7:
       # If the content of the safesync_url appears to be an SVN rev and the
       # URL of the source appears to be git, we can only attempt to find out
       # if a revision is useful after we've cloned the original URL, so just
       # ignore for now.
       if (os.path.isdir(self.checkout_path) and
           scm.GIT.IsGitSvn(cwd=self.checkout_path)):
         local_head = scm.GIT.GetGitSvnHeadRev(cwd=self.checkout_path)
         if not local_head or local_head < int(rev):
+          try:
+            logging.debug('Looking for git-svn configuration optimizations.')
+            if scm.GIT.Capture(['config', '--get', 'svn-remote.svn.fetch'],
+                             cwd=self.checkout_path):
+              scm.GIT.Capture(['fetch'], cwd=self.checkout_path)
+          except subprocess2.CalledProcessError:
+            logging.debug('git config --get svn-remote.svn.fetch failed, '
+                          'ignoring possible optimization.')
           if options.verbose:
             print('Running git svn fetch. This might take a while.\n')
           scm.GIT.Capture(['svn', 'fetch'], cwd=self.checkout_path)
         sha1 = scm.GIT.GetSha1ForSvnRev(cwd=self.checkout_path, rev=rev)
         if not sha1:
           raise gclient_utils.Error(
               ( 'It appears that either your git-svn remote is incorrectly\n'
                 'configured or the revision in your safesync_url is\n'
                 'higher than git-svn remote\'s HEAD as we couldn\'t find a\n'
                 'corresponding git hash for SVN rev %s.' ) % rev)
@@ skipping 580 matching lines @@
       new_command.append('--force')
       if command[0] != 'checkout' and scm.SVN.AssertVersion('1.6')[0]:
         new_command.extend(('--accept', 'theirs-conflict'))
     elif options.manually_grab_svn_rev:
       new_command.append('--force')
       if command[0] != 'checkout' and scm.SVN.AssertVersion('1.6')[0]:
         new_command.extend(('--accept', 'postpone'))
     elif command[0] != 'checkout' and scm.SVN.AssertVersion('1.6')[0]:
       new_command.extend(('--accept', 'postpone'))
     return new_command