Test fixes and rebase conflicts, round 1

Conflicts:
	src/test/run-pass/task-stderr.rs

Author: alexcrichton

src/libcollections/string.rs

@@ -23,7 +23,6 @@ use core::mem;
 use core::ops::{self, Deref, Add, Index};
 use core::ptr;
 use core::slice;
-#[allow(deprecated)] use core::str::Str;
 use core::str::pattern::Pattern;
 use unicode::str as unicode_str;
 use unicode::str::Utf16Item;

src/libcollections/vec.rs

@@ -63,7 +63,7 @@ use core::ops::{Index, IndexMut, Deref, Add};
 use core::ops;
 use core::ptr;
 use core::ptr::Unique;
-use core::slice::{self, AsSlice};
+use core::slice;
 use core::isize;
 use core::usize;
 

src/libstd/dynamic_lib.rs

@@ -259,19 +259,14 @@ mod dl {
 
 #[cfg(target_os = "windows")]
 mod dl {
+    use prelude::v1::*;
+
     use ffi::OsStr;
-    use iter::Iterator;
     use libc;
     use libc::consts::os::extra::ERROR_CALL_NOT_IMPLEMENTED;
-    use ops::FnOnce;
     use sys::os;
     use os::windows::prelude::*;
-    use option::Option::{self, Some, None};
     use ptr;
-    use result::Result;
-    use result::Result::{Ok, Err};
-    use string::String;
-    use vec::Vec;
     use sys::c::compat::kernel32::SetThreadErrorMode;
 
     pub fn open(filename: Option<&OsStr>) -> Result<*mut u8, String> {

src/libstd/sys/windows/fs2.rs

@@ -12,7 +12,6 @@ use core::prelude::*;
 use io::prelude::*;
 use os::windows::prelude::*;
 
-use default::Default;
 use ffi::OsString;
 use fmt;
 use io::{self, Error, SeekFrom};

src/test/run-pass/task-stderr.rs

@@ -8,10 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// pretty-expanded FIXME #23616
-
-#![allow(unknown_features)]
-#![feature(box_syntax, old_io, std_misc, io, set_panic, set_stdio)]
+#![feature(box_syntax, set_stdio)]
 
 use std::io::prelude::*;
 use std::io;