Minor refactoring for Zone class and friends.

src/interface.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_INTERFACE_H_
 #define V8_INTERFACE_H_
 
 #include "src/ast-value-factory.h"
-#include "src/zone-inl.h"  // For operator new.
 
 namespace v8 {
 namespace internal {
 
 
 // This class implements the following abstract grammar of interfaces
 // (i.e. module types):
 //   interface ::= UNDETERMINED | VALUE | CONST | MODULE(exports)
 //   exports ::= {name : interface, ...}
 // A frozen type is one that is fully determined. Unification does not
@@ skipping 186 matching lines @@
   }
 
   void DoAdd(const void* name, uint32_t hash, Interface* interface, Zone* zone,
              bool* ok);
   void DoUnify(Interface* that, bool* ok, Zone* zone);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_INTERFACE_H_