Rip out most of our outdated modules implementation.

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index f8b91a913d4a3c443e8cca897ca8a30dadb60b6d..26c73062f8ad05b8610bdb2c0d19779aeceaa273 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -412,10 +412,6 @@ class Factory final {
       PretenureFlag pretenure = NOT_TENURED,
       Handle<AllocationSite> allocation_site = Handle<AllocationSite>::null());
 
-  // JS modules are pretenured.
-  Handle<JSModule> NewJSModule(Handle<Context> context,
-                               Handle<ScopeInfo> scope_info);
-
   // JS arrays are pretenured when allocated by the parser.
 
   // Create a JSArray with a specified length and elements initialized