Replace ${name} with $name where possible.

pkg/analyzer/lib/src/generated/utilities_collection.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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.utilities.collection;
 
 import 'dart:collection';
@@ skipping 60 matching lines @@
   static int setEnum(int array, Enum index, bool value) => set(array, index.ordinal, value);
 
   /**
    * Throw an exception if the index is not within the bounds allowed for an integer-encoded array
    * of boolean values.
    *
    * @throws IndexOutOfBoundsException if the index is not between zero (0) and 31, inclusive
    */
   static void _checkIndex(int index) {
     if (index < 0 || index > 30) {
-      throw new RangeError("Index not between 0 and 30: ${index}");
+      throw new RangeError("Index not between 0 and 30: $index");
     }
   }
 }
 
 /**
  * Instances of the class `DirectedGraph` implement a directed graph in which the nodes are
  * arbitrary (client provided) objects and edges are represented implicitly. The graph will allow an
  * edge from any node to any other node, including itself, but will not represent multiple edges
  * between the same pair of nodes.
  *
@@ skipping 640 matching lines @@
 
   @override
   void set value(V newValue) {
     if (_currentKey == null) {
       throw new NoSuchElementException();
     }
     _currentValue = newValue;
     _map[_currentKey] = newValue;
   }
 }