[serializer] include global proxy in additional context snapshots.

test/cctest/test-lockers.cc

 // Copyright 2007-2011 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 668 matching lines @@
       count_(count),
       extension_names_(extension_names)
   {}
 
   virtual void Run() {
     v8::Isolate::CreateParams create_params;
     create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
     v8::Isolate* isolate = v8::Isolate::New(create_params);
     {
       v8::Isolate::Scope isolate_scope(isolate);
-      CHECK(
-          !reinterpret_cast<i::Isolate*>(isolate)->has_installed_extensions());
       v8::ExtensionConfiguration extensions(count_, extension_names_);
       v8::HandleScope handle_scope(isolate);
       v8::Context::New(isolate, &extensions);
-      CHECK(reinterpret_cast<i::Isolate*>(isolate)->has_installed_extensions());
     }
     isolate->Dispose();
   }
 
  private:
   int count_;
   const char** extension_names_;
 };
 
 
@@ skipping 27 matching lines @@
                                           kSimpleExtensionSource));
   const char* extension_names[] = { "test0", "test1",
                                     "test2", "test3", "test4",
                                     "test5", "test6", "test7" };
   i::List<JoinableThread*> threads(kNThreads);
   for (int i = 0; i < kNThreads; i++) {
     threads.Add(new IsolateGenesisThread(8, extension_names));
   }
   StartJoinAndDeleteThreads(threads);
 }