Eliminate RawObject::class_ field entirely.

runtime/vm/object.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_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 182 matching lines @@
   bool IsCanonical() const {
     ASSERT(!IsNull());
     return raw()->IsCanonical();
   }
   void SetCanonical() const {
     ASSERT(!IsNull());
     raw()->SetCanonical();
   }
 
   inline RawClass* clazz() const;
-  static intptr_t class_offset() { return OFFSET_OF(RawObject, class_); }
   static intptr_t tags_offset() { return OFFSET_OF(RawObject, tags_); }
 
   // Class testers.
 #define DEFINE_CLASS_TESTER(clazz)                                             \
   virtual bool Is##clazz() const { return false; }
 CLASS_LIST_NO_OBJECT(DEFINE_CLASS_TESTER);
 #undef DEFINE_CLASS_TESTER
 
   bool IsNull() const { return raw_ == null_; }
 
@@ skipping 4745 matching lines @@
 }
 
 
 intptr_t Stackmap::SizeInBits() const {
   return (Smi::Value(raw_ptr()->bitmap_size_in_bytes_) * kBitsPerByte);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_