Support for global var shortcuts in script contexts.

src/scopes.h

Index: src/scopes.h
diff --git a/src/scopes.h b/src/scopes.h
index fac8a5622d440d1a4a6db537839d297089d77091..f5a1bd97c6704521c721c3bc1a18a1233c036ce1 100644
--- a/src/scopes.h
+++ b/src/scopes.h
@@ -449,6 +449,7 @@ class Scope: public ZoneObject {
   // handled separately.
   void CollectStackAndContextLocals(
       ZoneList<Variable*>* stack_locals, ZoneList<Variable*>* context_locals,
+      ZoneList<Variable*>* context_globals,
       ZoneList<Variable*>* strong_mode_free_variables = nullptr);
 
   // Current number of var or const locals.
@@ -457,9 +458,11 @@ class Scope: public ZoneObject {
   // Result of variable allocation.
   int num_stack_slots() const { return num_stack_slots_; }
   int num_heap_slots() const { return num_heap_slots_; }
+  int num_global_slots() const { return num_global_slots_; }
 
   int StackLocalCount() const;
   int ContextLocalCount() const;
+  int ContextGlobalCount() const;
 
   // For script scopes, the number of module literals (including nested ones).
   int num_modules() const { return num_modules_; }
@@ -626,6 +629,7 @@ class Scope: public ZoneObject {
   // Computed via AllocateVariables; function, block and catch scopes only.
   int num_stack_slots_;
   int num_heap_slots_;
+  int num_global_slots_;
 
   // The number of modules (including nested ones).
   int num_modules_;
@@ -722,7 +726,8 @@ class Scope: public ZoneObject {
   void AllocateHeapSlot(Variable* var);
   void AllocateParameterLocals(Isolate* isolate);
   void AllocateNonParameterLocal(Isolate* isolate, Variable* var);
-  void AllocateNonParameterLocals(Isolate* isolate);
+  void AllocateDeclaredGlobal(Isolate* isolate, Variable* var);
+  void AllocateNonParameterLocalsAndDeclaredGlobals(Isolate* isolate);
   void AllocateVariablesRecursively(Isolate* isolate);
   void AllocateParameter(Variable* var, int index);
   void AllocateReceiver();