Remove python 2.5 compatibility code.

presubmit_support.py

Index: presubmit_support.py
diff --git a/presubmit_support.py b/presubmit_support.py
index 0b72f4656b72480d28e72283faa7997749a090c5..75977553d22d281e6af777f1d99834f8c9e58c54 100755
--- a/presubmit_support.py
+++ b/presubmit_support.py
@@ -17,6 +17,7 @@ import cStringIO  # Exposed through the API.
 import fnmatch
 import glob
 import inspect
+import json  # Exposed through the API.
 import logging
 import marshal  # Exposed through the API.
 import optparse
@@ -33,16 +34,6 @@ import unittest  # Exposed through the API.
 import urllib2  # Exposed through the API.
 from warnings import warn
 
-try:
-  import simplejson as json  # pylint: disable=F0401
-except ImportError:
-  try:
-    import json  # pylint: disable=F0401
-  except ImportError:
-    # Import the one included in depot_tools.
-    sys.path.append(os.path.join(os.path.dirname(__file__), 'third_party'))
-    import simplejson as json  # pylint: disable=F0401
-
 # Local imports.
 import fix_encoding
 import gclient_utils