Add automatic retry on "git remote update".

gclient_scm.py

 # 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.
 
 """Gclient-specific SCM-specific operations."""
 
 import logging
 import os
 import posixpath
 import re
@@ skipping 233 matching lines @@
     upstream_branch = self.GetUpstream(self.checkout_path)
     if not upstream_branch or not upstream_branch.startswith('refs/remotes'):
       current_type = "hash"
       logging.debug("Current branch is based off a specific rev and is not "
                     "tracking an upstream.")
     elif upstream_branch.startswith('refs/remotes'):
       current_type = "branch"
     else:
       raise gclient_utils.Error('Invalid Upstream')
 
-    # Update the remotes first so we have all the refs
-    remote_output, remote_err = self.Capture(['remote'] + verbose + ['update'],
-                                             self.checkout_path,
-                                             print_error=False)
+    # Update the remotes first so we have all the refs.
+    for i in range(3):
+      try:
+        remote_output, remote_err = self.Capture(
+            ['remote'] + verbose + ['update'],
+            self.checkout_path,
+            print_error=False)
+        break
+      except gclient_utils.CheckCallError, e:
+        # Hackish but at that point, git is known to work so just checking for
+        # 502 in stderr should be fine.
+        if '502' in e.stderr:
+          print str(e)
+          print "Retrying..."
+          continue
+        raise e
+
     if verbose:
       print remote_output.strip()
       # git remote update prints to stderr when used with --verbose
       print remote_err.strip()
 
     # This is a big hammer, debatable if it should even be here...
     if options.force or options.reset:
       self._Run(['reset', '--hard', 'HEAD'], redirect_stdout=False)
 
     if current_type is 'hash':
@@ skipping 547 matching lines @@
       print("\n________ couldn't run \'%s\' in \'%s\':\nThe directory "
             "does not exist."
             % (' '.join(command), path))
       # There's no file list to retrieve.
     else:
       self.RunAndGetFileList(options, command, path, file_list)
 
   def FullUrlForRelativeUrl(self, url):
     # Find the forth '/' and strip from there. A bit hackish.
     return '/'.join(self.url.split('/')[:4]) + url