Add libjingle_xmpp_unittests to Chromium bots.

testing/buildbot/gn_isolate_map.pyl

 ## Copyright 2015 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.
 
 # This is a .pyl, or "Python Literal", file. You can treat it just like a
 # .json file, with the following exceptions:
 # * all keys must be quoted (use single quotes, please);
 # * comments are allowed, using '#' syntax; and
 # * trailing commas are allowed.
 
@@ skipping 605 matching lines @@
   },
   "leveldb_service_unittests": {
     "label": "//components/leveldb:leveldb_service_unittests",
     "type": "console_test_launcher",
   },
   # See http://crbug.com/585151
   "libaddressinput_unittests": {
     "label": "//third_party/libaddressinput:libaddressinput_unittests",
     "type": "console_test_launcher",
   },
+  "libjingle_xmpp_unittests": {
+    "label": "//third_party/libjingle_xmpp:libjingle_xmpp_unittests",
+    "type": "console_test_launcher",
+  },
   # See http://crbug.com/585151
   "libphonenumber_unittests": {
     "label": "//third_party/libphonenumber:libphonenumber_unittests",
     "type": "console_test_launcher",
   },
   "mac_installer_unittests": {
     "label": "//chrome/installer/mac/app:mac_installer_unittests",
     "type": "console_test_launcher",
   },
   "mash:all" : {
@@ skipping 468 matching lines @@
   },
   "wm_unittests": {
     "label": "//ui/wm:wm_unittests",
     "type": "windowed_test_launcher",
   },
   "wtf_unittests": {
     "label": "//third_party/WebKit/Source/platform/wtf:wtf_unittests",
     "type": "console_test_launcher",
   },
 }