Revert of Remove {media,p2p,pc,xmllite,xmpp}_tests.gypi files.

webrtc/libjingle/xmpp/xmpp_tests.gypi

+# Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+#
+# Use of this source code is governed by a BSD-style license
+# that can be found in the LICENSE file in the root of the source
+# tree. An additional intellectual property rights grant can be found
+# in the file PATENTS.  All contributing project authors may
+# be found in the AUTHORS file in the root of the source tree.
+
+{
+  'includes': [ '../../build/common.gypi', ],
+  'targets': [
+    {
+      'target_name': 'rtc_xmpp_unittest',
+      'type': 'none',
+      'direct_dependent_settings': {
+        'sources': [
+          'fakexmppclient.h',
+          'hangoutpubsubclient_unittest.cc',
+          'jid_unittest.cc',
+          'mucroomconfigtask_unittest.cc',
+          'mucroomdiscoverytask_unittest.cc',
+          'mucroomlookuptask_unittest.cc',
+          'mucroomuniquehangoutidtask_unittest.cc',
+          'pingtask_unittest.cc',
+          'pubsubclient_unittest.cc',
+          'pubsubtasks_unittest.cc',
+          'util_unittest.cc',
+          'util_unittest.h',
+          'xmppengine_unittest.cc',
+          'xmpplogintask_unittest.cc',
+          'xmppstanzaparser_unittest.cc',
+        ],
+      },
+    },
+  ],
+}
+