Introduce a v8::Platform class that bundles embedder callbacks

include/v8.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 87 matching lines @@
 class HeapProfiler;
 class ImplementationUtilities;
 class Int32;
 class Integer;
 class Isolate;
 class Number;
 class NumberObject;
 class Object;
 class ObjectOperationDescriptor;
 class ObjectTemplate;
+class Platform;
 class Primitive;
 class RawOperationDescriptor;
 class Signature;
 class StackFrame;
 class StackTrace;
 class String;
 class StringObject;
 class Symbol;
 class SymbolObject;
 class Private;
@@ skipping 4653 matching lines @@
    * V8 had a chance to clean up.
    */
   static int ContextDisposedNotification();
 
   /**
    * Initialize the ICU library bundled with V8. The embedder should only
    * invoke this method when using the bundled ICU. Returns true on success.
    */
   static bool InitializeICU();
 
+  /**
+   * Sets the v8::Platform to use. This should be invoked before V8 is
+   * initialized.
+   */
+  static void InitializePlatform(Platform* platform);
+
+  /**
+   * Clears all references to the v8::Platform. This should be invoked after
+   * V8 was disposed.
+   */
+  static void ShutdownPlatform();
+
  private:
   V8();
 
   static internal::Object** GlobalizeReference(internal::Isolate* isolate,
                                                internal::Object** handle);
   static internal::Object** CopyPersistent(internal::Object** handle);
   static void DisposeGlobal(internal::Object** global_handle);
   typedef WeakReferenceCallbacks<Value, void>::Revivable RevivableCallback;
   typedef WeakCallbackData<Value, void>::Callback WeakCallback;
   static void MakeWeak(internal::Object** global_handle,
@@ skipping 1753 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_