Have fetch set up tag fetch refspecs.

fetch.py

 #!/usr/bin/env python
 # Copyright (c) 2013 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.
 
 """
 Tool to perform checkouts in one easy command line!
 
 Usage:
   fetch <recipe> [--property=value [--property2=value2 ...]]
@@ skipping 106 matching lines @@
       self.run_gclient('sync')
 
     # Configure git.
     wd = os.path.join(self.base, self.root)
     if self.options.dry_run:
       print 'cd %s' % wd
     self.run_git(
         'submodule', 'foreach',
         'git config -f $toplevel/.git/config submodule.$name.ignore all',
         cwd=wd)
+    self.run_git(
+        'config', '--add', 'remote.origin.fetch',
+        '+refs/tags/*:refs/tags/*', cwd=wd)
     self.run_git('config', 'diff.ignoreSubmodules', 'all', cwd=wd)
 
 
 class GclientGitSvnCheckout(GclientGitCheckout, SvnCheckout):
 
   def __init__(self, options, spec, root):
     super(GclientGitSvnCheckout, self).__init__(options, spec, root)
     assert 'svn_url' in self.spec
     assert 'svn_branch' in self.spec
     assert 'svn_ref' in self.spec
@@ skipping 150 matching lines @@
 
 
 def main():
   options, recipe, props = handle_args(sys.argv)
   spec, root = run_recipe_fetch(recipe, props)
   return run(options, spec, root)
 
 
 if __name__ == '__main__':
   sys.exit(main())