First version of typr propagation in the new IR.

pkg/compiler/lib/src/cps_ir/shrinking_reductions.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart2js.optimizers;
 
 /**
- * [[ShrinkingReducer]] applies shrinking reductions to CPS terms as described
+ * [ShrinkingReducer] applies shrinking reductions to CPS terms as described
  * in 'Compiling with Continuations, Continued' by Andrew Kennedy.
  */
 class ShrinkingReducer extends Pass {
   _RedexVisitor _redexVisitor;
   Set<_ReductionTask> _worklist;
 
   static final _DeletedNode _DELETED = new _DeletedNode();
 
   void rewriteExecutableDefinition(ExecutableDefinition root) {
     _worklist = new Set<_ReductionTask>();
@@ skipping 431 matching lines @@
   }
 
   String toString() => "$kind: $node";
 }
 
 /// A dummy class used solely to mark nodes as deleted once they are removed
 /// from a term.
 class _DeletedNode extends Node {
   accept(_) => null;
 }