Rename rustc_serialize::opaque::Encoder as MemEncoder.

This avoids the name clash with `rustc_serialize::Encoder` (a trait),
and allows lots qualifiers to be removed and imports to be simplified
(e.g. fewer `as` imports).

(This was previously merged as commit 5 in #94732 and then was reverted
in #97905 because of a perf regression caused by commit 4 in #94732.)

1 files changed, 3 insertions, 3 deletions

diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 4e2495ab14c..e5b61d7000a 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -31,7 +31,7 @@ use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_macros::HashStable_Generic;
-use rustc_serialize::{self, Decoder, Encoder};
+use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 use rustc_span::source_map::{respan, Spanned};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
@@ -2488,11 +2488,11 @@ rustc_index::newtype_index! {
     }
 }
 
-impl<S: Encoder> rustc_serialize::Encodable<S> for AttrId {
+impl<S: Encoder> Encodable<S> for AttrId {
     fn encode(&self, _s: &mut S) {}
 }
 
-impl<D: Decoder> rustc_serialize::Decodable<D> for AttrId {
+impl<D: Decoder> Decodable<D> for AttrId {
     fn decode(_: &mut D) -> AttrId {
         crate::attr::mk_attr_id()
     }