Replace fields with getters in keepalive API

General guidance is to have getters in the API instead of fields.

Fixes: 181014882
Test: m
Change-Id: Id4bfc447701e8d0380163047779fbba043f17b6f
diff --git a/framework/api/system-current.txt b/framework/api/system-current.txt
index 0a82cb7..d6d3888 100644
--- a/framework/api/system-current.txt
+++ b/framework/api/system-current.txt
@@ -455,14 +455,14 @@
   public final class TcpKeepalivePacketData extends android.net.KeepalivePacketData implements android.os.Parcelable {
     ctor public TcpKeepalivePacketData(@NonNull java.net.InetAddress, int, @NonNull java.net.InetAddress, int, @NonNull byte[], int, int, int, int, int, int) throws android.net.InvalidPacketException;
     method public int describeContents();
+    method public int getIpTos();
+    method public int getIpTtl();
+    method public int getTcpAck();
+    method public int getTcpSeq();
+    method public int getTcpWindow();
+    method public int getTcpWindowScale();
     method public void writeToParcel(@NonNull android.os.Parcel, int);
     field @NonNull public static final android.os.Parcelable.Creator<android.net.TcpKeepalivePacketData> CREATOR;
-    field public final int ipTos;
-    field public final int ipTtl;
-    field public final int tcpAck;
-    field public final int tcpSeq;
-    field public final int tcpWindow;
-    field public final int tcpWindowScale;
   }
 
 }