NetworkManagementService: receive bandwidth controller events

This is a 1st pass at receiving events that indicate
some quota has been reached e.g. warning quota, data collection quota,
 cutoff quota,...

It needs:
  - new kernel with quota2 logging support
  - new net:bandwidthcontroller that supports
    . quota2,
    . setting alerts.
  - new NetlinkEvent/NetlinkManager/NetlinkHandler to process
     NETLINK NFLOG messages.

Change-Id: Ibfbb13512c5350cdee0e544ec14caa6f59812409
diff --git a/core/java/android/net/INetworkManagementEventObserver.aidl b/core/java/android/net/INetworkManagementEventObserver.aidl
index 4436e6e..a97f203 100644
--- a/core/java/android/net/INetworkManagementEventObserver.aidl
+++ b/core/java/android/net/INetworkManagementEventObserver.aidl
@@ -52,4 +52,14 @@
      * @param iface The interface.
      */
     void interfaceRemoved(String iface);
+
+    /**
+     * A networking quota limit has been reached. The quota might not
+     * be specific to an interface.
+     *
+     * @param limitName The name of the limit that triggered.
+     * @param iface The interface on which the limit was detected.
+     */
+    void limitReached(String limitName, String iface);
+
 }