Fixed a memory leak in v8 and another one in d8.

src/v8.cc

 // 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 97 matching lines @@
   // The isolate has to be torn down before clearing the LOperand
   // caches so that the optimizing compiler thread (if running)
   // doesn't see an inconsistent view of the lithium instructions.
   isolate->TearDown();
   delete isolate;
 
   ElementsAccessor::TearDown();
   LOperand::TearDownCaches();
   ExternalReference::TearDownMathExpData();
   RegisteredExtension::UnregisterAll();
+  Isolate::GlobalTearDown();
 
   is_running_ = false;
   has_been_disposed_ = true;
 
   delete call_completed_callbacks_;
   call_completed_callbacks_ = NULL;
 
   OS::TearDown();
 }
 
@@ skipping 151 matching lines @@
   SetUpJSCallerSavedCodeData();
   SamplerRegistry::SetUp();
   ExternalReference::SetUp();
 }
 
 void V8::InitializeOncePerProcess() {
   CallOnce(&init_once, &InitializeOncePerProcessImpl);
 }
 
 } }  // namespace v8::internal