Rollup merge of rust-lang#21654 - FlaPer87:unify-impls, r=alexcrichton

Please, look at each commit to see the current differences and the desired result.

Closes: rust-lang#20260

r? @alexcrichton

Author: barosl

src/libstd/sys/windows/pipe.rs

@@ -129,6 +129,9 @@ impl Drop for Event {
     }
 }
 
+unsafe impl Send for Event {}
+unsafe impl Sync for Event {}
+
 struct Inner {
     handle: libc::HANDLE,
     lock: Mutex<()>,
@@ -156,6 +159,9 @@ impl Drop for Inner {
     }
 }
 
+unsafe impl Send for Inner {}
+unsafe impl Sync for Inner {}
+
 unsafe fn pipe(name: *const u16, init: bool) -> libc::HANDLE {
     libc::CreateNamedPipeW(
         name,
@@ -220,9 +226,6 @@ pub struct UnixStream {
     write_deadline: u64,
 }
 
-unsafe impl Send for UnixStream {}
-unsafe impl Sync for UnixStream {}
-
 impl UnixStream {
     fn try_connect(p: *const u16) -> Option<libc::HANDLE> {
         // Note that most of this is lifted from the libuv implementation.
@@ -615,17 +618,11 @@ pub struct UnixAcceptor {
     deadline: u64,
 }
 
-unsafe impl Send for UnixAcceptor {}
-unsafe impl Sync for UnixAcceptor {}
-
 struct AcceptorState {
     abort: Event,
     closed: AtomicBool,
 }
 
-unsafe impl Send for AcceptorState {}
-unsafe impl Sync for AcceptorState {}
-
 impl UnixAcceptor {
     pub fn accept(&mut self) -> IoResult<UnixStream> {
         // This function has some funky implementation details when working with

src/libstd/sys/windows/tcp.rs

@@ -116,17 +116,13 @@ pub struct TcpAcceptor {
     deadline: u64,
 }
 
-unsafe impl Send for TcpAcceptor {}
-unsafe impl Sync for TcpAcceptor {}
-
 struct AcceptorInner {
     listener: TcpListener,
     abort: Event,
     accept: Event,
     closed: AtomicBool,
 }
 
-unsafe impl Send for AcceptorInner {}
 unsafe impl Sync for AcceptorInner {}
 
 impl TcpAcceptor {