This is the first pass at making GetIPConfigs asynchronous.

chrome/browser/chromeos/cros/cros_network_functions.h

Index: chrome/browser/chromeos/cros/cros_network_functions.h
diff --git a/chrome/browser/chromeos/cros/cros_network_functions.h b/chrome/browser/chromeos/cros/cros_network_functions.h
index a850d5127824a1d29ccd96b8320ce5806fb4341f..e52e8ffb31d8cd01fc2acf18958e715e2eda998f 100644
--- a/chrome/browser/chromeos/cros/cros_network_functions.h
+++ b/chrome/browser/chromeos/cros/cros_network_functions.h
@@ -53,7 +53,7 @@ typedef base::Callback<void(const std::string& modem_device_path,
 // Callback for asynchronous getters.
 typedef base::Callback<void(
     const std::string& path,
-    const base::DictionaryValue* properties)> NetworkPropertiesCallback;
+    scoped_ptr<base::DictionaryValue> properties)> NetworkPropertiesCallback;
 
 // Callback for network properties watchers.
 typedef base::Callback<void(
@@ -263,14 +263,21 @@ void CrosRequestCellularRegister(const std::string& device_path,
 // Returns false on failure and true on success.
 bool CrosSetOfflineMode(bool offline);
 
+// Gets a list of all the NetworkIPConfigs using a given device path,
+// and returns the information via callback.
+void CrosListIPConfigs(const std::string& device_path,
+                       const NetworkGetIPConfigsCallback& callback);
+
+// DEPRECATED, DO NOT USE: Use the asynchronous CrosListIPConfigs, above,
+// instead.
 // Gets a list of all the NetworkIPConfigs using a given device path.
-// Optionally, you can get ipconfig-paths and the hardware address.
-// Pass NULL as |ipconfig_paths| and |hardware_address| if you are not
-// interested in these values.
-bool CrosListIPConfigs(const std::string& device_path,
-                       NetworkIPConfigVector* ipconfig_vector,
-                       std::vector<std::string>* ipconfig_paths,
-                       std::string* hardware_address);
+// Optionally, you can get ipconfig-paths and the hardware address. Pass NULL as
+// |ipconfig_paths| and |hardware_address| if you are not interested in these
+// values.
+bool CrosListIPConfigsAndBlock(const std::string& device_path,
+                               NetworkIPConfigVector* ipconfig_vector,
+                               std::vector<std::string>* ipconfig_paths,
+                               std::string* hardware_address);
 
 // Adds a IPConfig of the given type to the device
 bool CrosAddIPConfig(const std::string& device_path, IPConfigType type);