gclient: Only _DeleteOrMove if the destination directory is non-empty

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."""
 
 from __future__ import print_function
 
 import logging
 import os
@@ skipping 334 matching lines @@
       revision = revision.replace(self.remote + '/', 'refs/heads/')
       rev_type = "branch"
     else:
       # hash is also a tag, only make a distinction at checkout
       rev_type = "hash"
 
     if (not os.path.exists(self.checkout_path) or
         (os.path.isdir(self.checkout_path) and
          not os.path.exists(os.path.join(self.checkout_path, '.git')))):
       if (os.path.isdir(self.checkout_path) and
-          not os.path.exists(os.path.join(self.checkout_path, '.git'))):
+          not os.path.exists(os.path.join(self.checkout_path, '.git')) and
+          os.listdir(self.checkout_path)):
         # This is a little hack to work around checkouts which are created
         # using "gclient config --name ."
         if not self.relpath == '.':
           self._DeleteOrMove(options.force)
       self._Clone(revision, url, options)
       self._UpdateBranchHeads(options, fetch=True)
       if file_list is not None:
         files = self._Capture(['ls-files']).splitlines()
         file_list.extend([os.path.join(self.checkout_path, f) for f in files])
       if not verbose:
@@ skipping 1095 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