Patch for mergeing 44671 to 1.9 branch, the whitespace changes makes it conflict big time

dart/runtime/lib/compact_hash.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:typed_data';
 
 // Hash table with open addressing that separates the index from keys/values.
 abstract class _HashBase {
   // Each occupied entry in _index is a fixed-size integer that encodes a pair:
   //   [ hash pattern for key | index of entry in _data ]
@@ skipping 67 matching lines @@
     assert(_HashBase._UNUSED_PAIR == 0);
     _index = new Uint32List(_HashBase._INITIAL_INDEX_SIZE);
     _data = new List(_HashBase._INITIAL_INDEX_SIZE);
   }
   
   int get length => (_usedData >> 1) - _deletedKeys;
   bool get isEmpty => length == 0;
   bool get isNotEmpty => !isEmpty;
   
   void _rehash() {
-    if ((_deletedKeys << 1) > _usedData) {
+    if ((_deletedKeys << 2) > _usedData) {
       // TODO(koda): Consider shrinking.
       // TODO(koda): Consider in-place compaction and more costly CME check.
       _init(_index.length, _hashMask, _data, _usedData);
     } else {
       // TODO(koda): Support 32->64 bit transition (and adjust _hashMask).
       _init(_index.length << 1, _hashMask >> 1, _data, _usedData);
     }
   }
   
   void clear() {
@@ skipping 365 matching lines @@
       pair = _index[i];
     }
     return false;
   }
                                                 
   Iterator<K> get iterator =>
       new _CompactIterator<K>(this, _data, _usedData, -1, 1);
 
   Set<K> toSet() => new Set<K>()..addAll(this);  
 }