Unhide RouteInfo#getType and related fields

Bug: 186082280
Test: atest RouteInfoTest
Change-Id: I59b9185cf4f8f2afd691b49cf6b4659fe36e6bf8
diff --git a/framework/api/current.txt b/framework/api/current.txt
index 9a77a3c..c53f29a 100644
--- a/framework/api/current.txt
+++ b/framework/api/current.txt
@@ -439,11 +439,15 @@
     method @NonNull public android.net.IpPrefix getDestination();
     method @Nullable public java.net.InetAddress getGateway();
     method @Nullable public String getInterface();
+    method public int getType();
     method public boolean hasGateway();
     method public boolean isDefaultRoute();
     method public boolean matches(java.net.InetAddress);
     method public void writeToParcel(android.os.Parcel, int);
     field @NonNull public static final android.os.Parcelable.Creator<android.net.RouteInfo> CREATOR;
+    field public static final int RTN_THROW = 9; // 0x9
+    field public static final int RTN_UNICAST = 1; // 0x1
+    field public static final int RTN_UNREACHABLE = 7; // 0x7
   }
 
   public abstract class SocketKeepalive implements java.lang.AutoCloseable {