Parsing of basic module declarations (no imports/exports yet).

src/contexts.h

Index: src/contexts.h
diff --git a/src/contexts.h b/src/contexts.h
index 1f88c946de964f4155863d51fed6d0b6c287fb61..af5cb036c615bb212a91aae4cd1a3bff808ec1ea 100644
--- a/src/contexts.h
+++ b/src/contexts.h
@@ -356,6 +356,10 @@ class Context: public FixedArray {
     Map* map = this->map();
     return map == map->GetHeap()->block_context_map();
   }
+  bool IsModuleContext() {
+    Map* map = this->map();
+    return map == map->GetHeap()->module_context_map();
+  }
 
   // Tells whether the global context is marked with out of memory.
   inline bool has_out_of_memory();