[Isolates] Fixing Win32 compile and running tests failure.

src/builtins.cc

 // Copyright 2006-2008 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 1361 matching lines @@
   Debug::GeneratePlainReturnLiveEdit(masm);
 }
 
 
 static void Generate_FrameDropper_LiveEdit(MacroAssembler* masm) {
   Debug::GenerateFrameDropperLiveEdit(masm);
 }
 #endif
 
 
-Builtins::Builtins() {
+Builtins::Builtins() : initialized_(false) {
   memset(builtins_, 0, sizeof(builtins_[0]) * builtin_count);
   memset(names_, 0, sizeof(names_[0]) * builtin_count);
 }
 
 
 Builtins::~Builtins() {
 }
 
 
 #define DEF_ENUM_C(name, ignore) FUNCTION_ADDR(Builtin_##name),
@@ skipping 159 matching lines @@
       if (entry->contains(pc)) {
         return names_[i];
       }
     }
   }
   return NULL;
 }
 
 
 } }  // namespace v8::internal