Added class to subscribe to GCD notifications over XMPP.

remoting/signaling/jid_util.h

 // 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.
 
 #ifndef REMOTING_SIGNALING_JID_UTIL_H_
 #define REMOTING_SIGNALING_JID_UTIL_H_
 
 #include <string>
 
 namespace remoting {
 
 // Normalizes the |jid| by converting case-insensitive parts (node and domain)
 // to lower-case.
 std::string NormalizeJid(const std::string& jid);
 
+// Splits a JID into a bare JID and a resource suffix.  Either or both
+// of |full_jid| and |resource| may be null.  If |full_jid| is already
+// a bare JID, |resource| is set to the empty string.  Returns true of
+// |full_jid| has a resource, false if not.
+//
+// e.g. "user@domain/resource" -> "user@domain", "resource", true
+//      "user@domain"          -> "user@domain", "",         false
+bool SplitJidResource(const std::string& full_jid,
+                      std::string* bare_jid,
+                      std::string* resource);
+
 }  // namespace remoting
 
 #endif  // REMOTING_SIGNALING_JID_UTIL_H_