Introduce global contexts to represent lexical global scope(s).

src/runtime.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 312 matching lines @@
   F(NewObjectFromBound, 1, 1) \
   F(FinalizeInstanceSize, 1, 1) \
   F(Throw, 1, 1) \
   F(ReThrow, 1, 1) \
   F(ThrowReferenceError, 1, 1) \
   F(StackGuard, 0, 1) \
   F(Interrupt, 0, 1) \
   F(PromoteScheduledException, 0, 1) \
   \
   /* Contexts */ \
+  F(NewGlobalContext, 2, 1) \
   F(NewFunctionContext, 1, 1) \
   F(PushWithContext, 2, 1) \
   F(PushCatchContext, 3, 1) \
   F(PushBlockContext, 2, 1) \
   F(PushModuleContext, 1, 1) \
   F(DeleteContextSlot, 2, 1) \
   F(LoadContextSlot, 2, 2) \
   F(LoadContextSlotNoReferenceError, 2, 2) \
   F(StoreContextSlot, 4, 1) \
   \
@@ skipping 371 matching lines @@
 //---------------------------------------------------------------------------
 // Constants used by interface to runtime functions.
 
 class DeclareGlobalsEvalFlag:     public BitField<bool,         0, 1> {};
 class DeclareGlobalsNativeFlag:   public BitField<bool,         1, 1> {};
 class DeclareGlobalsLanguageMode: public BitField<LanguageMode, 2, 2> {};
 
 } }  // namespace v8::internal
 
 #endif  // V8_RUNTIME_H_