Reapply r186598 with fix for 'gclient revert'.

gclient_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.
 
 """Gclient-specific SCM-specific operations."""
 
 import logging
 import os
 import posixpath
 import re
@@ skipping 637 matching lines @@
       print('')
 
     clone_cmd = ['clone', '--progress']
     if revision.startswith('refs/heads/'):
       clone_cmd.extend(['-b', revision.replace('refs/heads/', '')])
       detach_head = False
     else:
       detach_head = True
     if options.verbose:
       clone_cmd.append('--verbose')
+    # Don't assume 'with_branch_heads' is added by 'gclient sync' setup, since
+    # _Clone() can by reached in roundabout ways (e.g. 'gclient revert').
+    if hasattr(options, 'with_branch_heads') and options.with_branch_heads:
+      clone_cmd.extend(['--config', 'remote.origin.fetch=+refs/branch-heads/*:'
+                        'refs/remotes/branch-heads/*'])
     clone_cmd.extend([url, self.checkout_path])
 
     # If the parent directory does not exist, Git clone on Windows will not
     # create it, so we need to do it manually.
     parent_dir = os.path.dirname(self.checkout_path)
     if not os.path.exists(parent_dir):
       gclient_utils.safe_makedirs(parent_dir)
 
     percent_re = re.compile('.* ([0-9]{1,2})% .*')
     def _GitFilter(line):
       # git uses an escape sequence to clear the line; elide it.
       esc = line.find(unichr(033))
       if esc > -1:
         line = line[:esc]
       match = percent_re.match(line)
       if not match or not int(match.group(1)) % 10:
         print '%s' % line
 
     for _ in range(3):
       try:
         self._Run(clone_cmd, options, cwd=self._root_dir, filter_fn=_GitFilter,
                   print_stdout=False)
+        # Update the "branch-heads" remote-tracking branches, since clone
+        # doesn't automatically fetch those, and we might need it to checkout a
+        # specific revision below.
+        if (hasattr(options, 'with_branch_heads') and
+            options.with_branch_heads):
+          fetch_cmd = ['fetch', 'origin']
+          if options.verbose:
+            fetch_cmd.append('--verbose')
+          self._Run(fetch_cmd, options)
         break
       except subprocess2.CalledProcessError, e:
         # Too bad we don't have access to the actual output yet.
         # We should check for "transfer closed with NNN bytes remaining to
         # read". In the meantime, just make sure .git exists.
         if (e.returncode == 128 and
             os.path.exists(os.path.join(self.checkout_path, '.git'))):
           print(str(e))
           print('Retrying...')
           continue
@@ skipping 535 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