Remove most superfluous getter arguments from dart2js.

dart/lib/compiler/implementation/ssa/value_set.dart

 // Copyright (c) 2012, 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.
 
 class ValueSet {
   int size = 0;
   List<HInstruction> table;
   ValueSetNode collisions;
   ValueSet() : table = new List<HInstruction>(8);
 
   bool isEmpty() => size == 0;
-  int get length() => size;
+  int get length => size;
 
   void add(HInstruction instruction) {
     assert(lookup(instruction) === null);
     int hashCode = instruction.gvnHashCode();
     int capacity = table.length;
     // Resize when half of the hash table is in use.
     if (size >= capacity >> 1) {
       capacity = capacity << 1;
       resize(capacity);
     }
@@ skipping 122 matching lines @@
     assert(table.length == capacity);
   }
 }
 
 class ValueSetNode {
   final HInstruction value;
   final int hashCode;
   ValueSetNode next;
   ValueSetNode(this.value, this.hashCode, this.next);
 }