Speedup global_proxy.* attributes/accessors (specialize GlobalProxy access).

src/crankshaft/hydrogen.h

Index: src/crankshaft/hydrogen.h
diff --git a/src/crankshaft/hydrogen.h b/src/crankshaft/hydrogen.h
index ac4d6e968218f12439a1cb5e0c9d05ed30e7c7a9..1e88fb6470c7831fda0d44cb584b6aea1a28e387 100644
--- a/src/crankshaft/hydrogen.h
+++ b/src/crankshaft/hydrogen.h
@@ -2360,13 +2360,13 @@ class HOptimizedGraphBuilder : public HGraphBuilder,
 #undef DECLARE_VISIT
 
  private:
-  // Helpers for flow graph construction.
-  enum GlobalPropertyAccess {
-    kUseCell,
-    kUseGeneric
-  };
-  GlobalPropertyAccess LookupGlobalProperty(Variable* var, LookupIterator* it,
-                                            PropertyAccessType access_type);
+  bool LookupGlobalPropertyCell(Variable* var, LookupIterator* it,
+                                PropertyAccessType access_type);
+
+  bool LookupGlobalPropertyCell(LookupIterator* it,
+                                PropertyAccessType access_type);
+
+  void LoadFromCell(LookupIterator* it, BailoutId ast_id);
 
   void EnsureArgumentsArePushedForAccess();
   bool TryArgumentsAccess(Property* expr);