[Isolates] Replace ISOLATE_FROM_HEAP with Heap::isolate()

src/isolate.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1017 matching lines @@
 #undef GLOBAL_ARRAY_BACKING_STORE
 
   friend class IsolateInitializer;
   friend class v8::Isolate;
   friend class v8::Locker;
 
   DISALLOW_COPY_AND_ASSIGN(Isolate);
 };
 
 
-#define ISOLATE_FROM_HEAP(heap_pointer) ((Isolate*)(  \
-  (uint8_t*)(heap_pointer) -                          \
-  (size_t)((Isolate*)sizeof(Isolate))->heap() +       \
-  sizeof(Isolate)))
-
-
 // If the GCC version is 4.1.x or 4.2.x an additional field is added to the
 // class as a work around for a bug in the generated code found with these
 // versions of GCC. See V8 issue 122 for details.
 class SaveContext BASE_EMBEDDED {
  public:
   SaveContext()
       : context_(Isolate::Current()->context()),
 #if __GNUC_VERSION__ >= 40100 && __GNUC_VERSION__ < 40300
         dummy_(Isolate::Current()->context()),
 #endif
@@ skipping 126 matching lines @@
 #define ISOLATED_CLASS class
 
 } }  // namespace v8::internal
 
 // TODO(isolates): Get rid of these -inl.h includes and place them only where
 //                 they're needed.
 #include "allocation-inl.h"
 #include "zone-inl.h"
 
 #endif  // V8_ISOLATE_H_