Revert "librustc: Make unqualified identifier searches terminate at the nearest module scope. r=tjc"

This reverts commit a8d37af247.

src/libstd/json.rs

@@ -23,7 +23,6 @@ use core::cmp::{Eq, Ord};
 use core::float;
 use core::io::{WriterUtil, ReaderUtil};
 use core::io;
-use core::prelude::*;
 use core::send_map::linear;
 use core::str;
 use core::to_str;
@@ -1194,10 +1193,6 @@ impl Error: to_str::ToStr {
 
 #[cfg(test)]
 mod tests {
-    use core::prelude::*;
-
-    use json::*;
-
     use core::result;
     use core::send_map::linear;