Remove import of collection-dev.

pkg/serialization/lib/src/format.dart

 part of serialization;
 
 /**
  * An abstract class for serialization formats. Subclasses define how data
  * is read or written to a particular output mechanism.
  */
 abstract class Format {
   /**
    * Return true if this format stores primitives in their own area and uses
    * references to them (e.g. [SimpleFlatFormat]) and false if primitives
@@ skipping 166 matching lines @@
       return data;
     }
     var ruleNumber;
     if (data is List) {
       ruleNumber = data.removeLast();
     } else if (data is Map) {
       ruleNumber = data.remove(ruleIdentifier);
     } else {
       throw new SerializationException("Invalid data format");
     }
-    var newData = values(data).mappedBy(
-        (x) => recursivelyFixUp(x, r, result));
-    // TODO(alanknight): Ugh. Get rid of this if we can resolve bug 7982/7940.
-    if (newData is MappedList) {
-      newData = newData.toList();
-    }
+    var newData = mapValues(data, (x) => recursivelyFixUp(x, r, result));
     result[ruleNumber].add(newData);
     return new Reference(r, ruleNumber, result[ruleNumber].length - 1);
   }
 }
 
 /**
  * Writes to a simple mostly-flat format. Details are subject to change.
  * Right now this produces a List containing null, num, and String. This is
  * more space-efficient than the map formats, but much less human-readable.
  * Simple usage is to turn this into JSON for transmission.
@@ skipping 230 matching lines @@
       return new Reference(r, a, b);
     }
   }
 
   /** Return the next element from the input. */
   _next(Iterator input) {
     input.moveNext();
     return input.current;
   }
 }