Replace HashUtil w/ default method on Hash

Author: jfager

src/librustc/metadata/decoder.rs

@@ -25,7 +25,6 @@ use middle::typeck;
 use middle::astencode::vtable_decoder_helpers;
 
 
-use std::hash::HashUtil;
 use std::u64;
 use std::io::WriterUtil;
 use std::io;

src/librustc/metadata/encoder.rs

@@ -21,7 +21,6 @@ use middle::typeck;
 use middle::astencode;
 use middle;
 
-use std::hash::HashUtil;
 use std::hashmap::{HashMap, HashSet};
 use std::io;
 use std::str;

src/libstd/hash.rs

@@ -59,14 +59,7 @@ pub trait Hash {
      * IterBytes trait, that feeds SipHash.
      */
     fn hash_keyed(&self, k0: u64, k1: u64) -> u64;
-}
-
-// When we have default methods, won't need this.
-pub trait HashUtil {
-    fn hash(&self) -> u64;
-}
 
-impl<A:Hash> HashUtil for A {
     #[inline]
     fn hash(&self) -> u64 { self.hash_keyed(0,0) }
 }

src/test/run-pass/deriving-meta-multiple.rs

@@ -19,8 +19,6 @@ struct Foo {
 }
 
 pub fn main() {
-    use std::hash::HashUtil; // necessary for IterBytes check
-
     let a = Foo {bar: 4, baz: -3};
 
     a == a;    // check for Eq impl w/o testing its correctness

src/test/run-pass/deriving-meta.rs

@@ -17,8 +17,6 @@ struct Foo {
 }
 
 pub fn main() {
-    use std::hash::HashUtil; // necessary for IterBytes check
-
     let a = Foo {bar: 4, baz: -3};
 
     a == a;    // check for Eq impl w/o testing its correctness