Add env variable to suppress the notice about deprecated SVN

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 errno
 import logging
@@ skipping 1151 matching lines @@
 class SVNWrapper(SCMWrapper):
   """ Wrapper for SVN """
   name = 'svn'
   _PRINTED_DEPRECATION = False
 
   _MESSAGE = (
     'Oh hai! You are using subversion. Chrome infra is eager to get rid of',
     'svn support so please switch to git.',
     'Tracking bug: http://crbug.com/475320',
     'Request a new git repository at: ',
-    '  https://code.google.com/p/chromium/issues/entry?template=Infra-Git',
-    '',
-    'If subversion support is needed, pin your depot_tools to ',
-    'c20f470011e2ea4d81527976f3bded2c13e258af and set the env var',
-    'DEPOT_TOOLS_UPDATE=0',
-    'Thank you for your business!')
+    '  https://code.google.com/p/chromium/issues/entry?template=Infra-Git')
 
   def __init__(self, *args, **kwargs):
     super(SVNWrapper, self).__init__(*args, **kwargs)
-    if not SVNWrapper._PRINTED_DEPRECATION:
+    suppress_deprecated_notice = os.environ.get(
+        'SUPPRESS_DEPRECATED_SVN_NOTICE', False)
+    if not SVNWrapper._PRINTED_DEPRECATION and not suppress_deprecated_notice:
       SVNWrapper._PRINTED_DEPRECATION = True
       sys.stderr.write('\n'.join(self._MESSAGE) + '\n')
 
   @staticmethod
   def BinaryExists():
     """Returns true if the command exists."""
     try:
       result, version = scm.SVN.AssertVersion('1.4')
       if not result:
         raise gclient_utils.Error('SVN version is older than 1.4: %s' % version)
@@ skipping 448 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