Add "not congested" network capability.

Can be used by a network to indicate when it's congested, meaning that
apps should defer network traffic that could be done at a later time.

Test: bit FrameworksNetTests:android.net.,com.android.server.net.,com.android.server.connectivity.VpnTest,com.android.server.ConnectivityServiceTest
Bug: 64133169
Change-Id: I97664d041920c8d6e3f9fb7c9e8638925b15c30e
diff --git a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
index 0bbe3b5..2e5d09e 100644
--- a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
+++ b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
@@ -429,6 +429,7 @@
         mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
         mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED);
         mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING);
+        mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED);
         mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
         // We have no useful data on bandwidth. Say 100M up and 100M down. :-(
         mNetworkCapabilities.setLinkUpstreamBandwidthKbps(100 * 1000);