DEPS bump to pull in latest linter.

DEPS

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 vars = {
   # The dart_root is the root of our sdk checkout. This is normally
   # simply sdk, but if using special gclient specs it can be different.
   "dart_root": "sdk",
 
   # The svn location to pull out dependencies from
@@ skipping 50 matching lines @@
   "gsutil_rev" : "@33376",
   "html_tag" : "@0.12.1+1",
   "http_rev" : "@9b93e1542c753090c50b46ef1592d44bc858bfe7",
   "http_multi_server_tag" : "@1.3.2",
   "http_parser_rev" : "@8b179e36aba985208e4c5fb15cfddd386b6370a4",
   "http_throttle_rev" : "@a81f08be942cdd608883c7b67795c12226abc235",
   "idl_parser_rev": "@6316d5982dc24b34d09dd8b10fbeaaff28d83a48",
   "intl_rev": "@32047558bd220a53c1f4d93a26d54b83533b1475",
   "jinja2_rev": "@2222b31554f03e62600cd7e383376a7c187967a1",
   "json_rpc_2_tag": "@1.1.1",
-  "linter_rev": "@b01bba400d28925e4610a2f472581b686d06c3c6",
+  "linter_rev": "@b638cb3048fdcaebc18b847257355bfc34efe139",
   "logging_rev": "@85d83e002670545e9039ad3985f0018ab640e597",
   "markdown_rev": "@4aaadf3d940bb172e1f6285af4d2b1710d309982",
   "matcher_tag": "@0.12.0",
   "metatest_rev": "@e5aa8e4e19fc4188ac2f6d38368a47d8f07c3df1",
   "mime_rev": "@75890811d4af5af080351ba8a2853ad4c8df98dd",
   "mustache4dart_rev" : "@5724cfd85151e5b6b53ddcd3380daf188fe47f92",
   "oauth2_rev": "@1bff41f4d54505c36f2d1a001b83b8b745c452f5",
   "observe_rev": "@eee2b8ec34236fa46982575fbccff84f61202ac6",
   "observatory_pub_packages_rev": "@a731d3b1caf27b45aecdce9378b87a510240264d",
   "package_config_rev": "@0.1.3",
@@ skipping 303 matching lines @@
       "--bucket",
       "dart-dependencies",
       "--recursive",
       "--auto_platform",
       "--extract",
       "--directory",
       Var('dart_root') + "/tools/sdks",
     ],
   },
 ]