Add SortedMap to rustc_data_structures.

Author: michaelwoerister

src/librustc_data_structures/lib.rs

@@ -73,6 +73,7 @@ pub mod control_flow_graph;
 pub mod flock;
 pub mod sync;
 pub mod owning_ref;
+pub mod sorted_map;
 
 pub struct OnDrop<F: Fn()>(pub F);