[CrOS Tether] Create the ActiveHost class, which stores metadata related to the current connection …

chromeos/components/tether/pref_names.h

Index: chromeos/components/tether/pref_names.h
diff --git a/chromeos/components/tether/pref_names.h b/chromeos/components/tether/pref_names.h
index 7f5b92370efecd021be33fbbb51feec4a6d00912..d6285b367d03b469177838efc6837b305081e6b8 100644
--- a/chromeos/components/tether/pref_names.h
+++ b/chromeos/components/tether/pref_names.h
@@ -22,6 +22,18 @@ extern const char kMostRecentTetherAvailablilityResponderIds[];
 // a response code indicating that its hotspot has started up successfully.
 extern const char kMostRecentConnectTetheringResponderId[];
 
+// The status of the active host. The value stored for this key is the integer
+// version of an ActiveHost::ActiveHostStatus enumeration value.
+extern const char kActiveHostStatus[];
+
+// The device ID of the active host. If there is no active host, the value at
+// this key is "".
+extern const char kActiveHostDeviceId[];
+
+// The Wi-Fi network ID of the active host. If there is no active host, the
+// value at this key is "".
+extern const char kWifiNetworkId[];
+
 }  // namespace prefs
 
 }  // namespace tether