Add WiFi SSID getter to NetworkChangeNotifier.

net/base/network_change_notifier.h

Index: net/base/network_change_notifier.h
diff --git a/net/base/network_change_notifier.h b/net/base/network_change_notifier.h
index 964fcf3c4b9a3a050a8030fe65da8bd0b4b0a304..72bc308454e775aef42cbe555fd9649cb4eab097 100644
--- a/net/base/network_change_notifier.h
+++ b/net/base/network_change_notifier.h
@@ -5,6 +5,7 @@
 #ifndef NET_BASE_NETWORK_CHANGE_NOTIFIER_H_
 #define NET_BASE_NETWORK_CHANGE_NOTIFIER_H_
 
+#include <string>
 #include <vector>
 
 #include "base/basictypes.h"
@@ -204,6 +205,10 @@ class NET_EXPORT NetworkChangeNotifier {
   // cheap as it is called often.
   virtual ConnectionType GetCurrentConnectionType() const = 0;
 
+  // See the description of NetworkChangeNotifier::GetConnectionType.
+  // Implementations must be thread-safe.
+  virtual std::string GetCurrentWiFiSSID() const = 0;
+
   // Replaces the default class factory instance of NetworkChangeNotifier class.
   // The method will take over the ownership of |factory| object.
   static void SetFactory(NetworkChangeNotifierFactory* factory);
@@ -228,6 +233,13 @@ class NET_EXPORT NetworkChangeNotifier {
   // the internet, the connection type is CONNECTION_WIFI.
   static ConnectionType GetConnectionType();
 
+  // Returns the SSID of the current Wi-Fi connection.
+  // A non empty string return value means that the current connection is a
+  // Wi-Fi connection. However, an empty string doesn't necessarily mean the
+  // connection isn't Wi-Fi, any error getting the SSID results in an empty
+  // string.
+  static std::string GetWiFiSSID();
+
   // Returns a theoretical upper limit on download bandwidth, potentially based
   // on underlying connection type, signal strength, or some other signal. The
   // default mapping of connection type to maximum bandwidth is provided in the