Tree-shaking: use a hash set for tracking live selectors, drop uncompiled functions.

runtime/vm/hash_map.h

 // 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.
 
 #ifndef VM_HASH_MAP_H_
 #define VM_HASH_MAP_H_
 
+#include "vm/zone.h"
+
 namespace dart {
 
 template <typename KeyValueTrait>
 class DirectChainedHashMap: public ValueObject {
  public:
   DirectChainedHashMap() : array_size_(0),
                            lists_size_(0),
                            count_(0),
                            array_(NULL),
                            lists_(NULL),
@@ skipping 223 matching lines @@
   }
 
   static inline bool IsKeyEqual(Pair kv, Key key) {
     return kv->Equals(key);
   }
 };
 
 }  // namespace dart
 
 #endif  // VM_HASH_MAP_H_