Revert r17907 - Make it possible to add more than one piece of embedder data to isolates

src/isolate.h

 // Copyright 2012 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 1032 matching lines @@
   }
 
   StateTag current_vm_state() {
     return thread_local_top_.current_vm_state_;
   }
 
   void set_current_vm_state(StateTag state) {
     thread_local_top_.current_vm_state_ = state;
   }
 
-  void SetData(uint32_t slot, void* data) {
-    ASSERT(slot < Internals::kNumIsolateDataSlots);
-    embedder_data_[slot] = data;
-  }
-  void* GetData(uint32_t slot) {
-    ASSERT(slot < Internals::kNumIsolateDataSlots);
-    return embedder_data_[slot];
-  }
+  void SetData(void* data) { embedder_data_ = data; }
+  void* GetData() { return embedder_data_; }
 
   LookupResult* top_lookup_result() {
     return thread_local_top_.top_lookup_result_;
   }
   void SetTopLookupResult(LookupResult* top) {
     thread_local_top_.top_lookup_result_ = top;
   }
 
   bool IsDead() { return has_fatal_error_; }
   void SignalFatalError() { has_fatal_error_ = true; }
@@ skipping 93 matching lines @@
 
   enum State {
     UNINITIALIZED,    // Some components may not have been allocated.
     INITIALIZED       // All components are fully initialized.
   };
 
   // These fields are accessed through the API, offsets must be kept in sync
   // with v8::internal::Internals (in include/v8.h) constants. This is also
   // verified in Isolate::Init() using runtime checks.
   State state_;  // Will be padded to kApiPointerSize.
-  void* embedder_data_[Internals::kNumIsolateDataSlots];
+  void* embedder_data_;
   Heap heap_;
 
   // The per-process lock should be acquired before the ThreadDataTable is
   // modified.
   class ThreadDataTable {
    public:
     ThreadDataTable();
     ~ThreadDataTable();
 
     PerIsolateThreadData* Lookup(Isolate* isolate, ThreadId thread_id);
@@ skipping 408 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_