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
1 file changed