Use ParcelDescriptor.fromSocket instead of getFileDescriptor

Socket.getFileDescriptor$ is a hidden API. Instead, replace it with
ParcelDescriptor.fromSocket, which was created to handle such use-cases.

Bug: 170598012
Change-Id: I9e218e4ec29d2b7fe5d2faeb1c2e1cafc63dc923
Test: m
diff --git a/framework/src/android/net/QosSocketInfo.java b/framework/src/android/net/QosSocketInfo.java
index d37c469..3bf700b 100644
--- a/framework/src/android/net/QosSocketInfo.java
+++ b/framework/src/android/net/QosSocketInfo.java
@@ -92,7 +92,7 @@
         Objects.requireNonNull(socket, "socket cannot be null");
 
         mNetwork = Objects.requireNonNull(network, "network cannot be null");
-        mParcelFileDescriptor = ParcelFileDescriptor.dup(socket.getFileDescriptor$());
+        mParcelFileDescriptor = ParcelFileDescriptor.fromSocket(socket);
         mLocalSocketAddress =
                 new InetSocketAddress(socket.getLocalAddress(), socket.getLocalPort());
     }