Rename StringNetworkSpecifier to Ethernet

The new specifier represents ethernet interfaces more
specifically and is part of the public API.

Bug: 179329291
Test: atest CtsNetTestCases
Merged-In: I6cba1709b3007a22d95849a1281237c77e1464a4
Change-Id: I6cba1709b3007a22d95849a1281237c77e1464a4
diff --git a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
index b9ebf89..dba152c 100644
--- a/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
+++ b/service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java
@@ -23,6 +23,7 @@
 import android.annotation.Nullable;
 import android.content.Context;
 import android.net.ConnectivityManager;
+import android.net.EthernetNetworkSpecifier;
 import android.net.IpConfiguration;
 import android.net.IpConfiguration.IpAssignment;
 import android.net.IpConfiguration.ProxySettings;
@@ -33,7 +34,6 @@
 import android.net.NetworkFactory;
 import android.net.NetworkRequest;
 import android.net.NetworkSpecifier;
-import android.net.StringNetworkSpecifier;
 import android.net.ip.IIpClient;
 import android.net.ip.IpClientCallbacks;
 import android.net.ip.IpClientUtil;
@@ -219,8 +219,9 @@
         String requestedIface = null;
 
         NetworkSpecifier specifier = request.getNetworkSpecifier();
-        if (specifier instanceof StringNetworkSpecifier) {
-            requestedIface = ((StringNetworkSpecifier) specifier).specifier;
+        if (specifier instanceof EthernetNetworkSpecifier) {
+            requestedIface = ((EthernetNetworkSpecifier) specifier)
+                .getInterfaceName();
         }
 
         NetworkInterfaceState network = null;