Rip out most of our outdated modules implementation.

src/contexts.h

Index: src/contexts.h
diff --git a/src/contexts.h b/src/contexts.h
index df592cee07b2c07d493495cb3b93add2cbdc6297..5068081805250504fa6d4d4f6232ccca2b37787b 100644
--- a/src/contexts.h
+++ b/src/contexts.h
@@ -349,7 +349,6 @@ class ScriptContextTable : public FixedArray {
 //                block scopes, it may also be a struct being a
 //                SloppyBlockWithEvalContextExtension, pairing the ScopeInfo
 //                with an extension object.
-//                For module contexts, points back to the respective JSModule.
 //
 // [ global_object ]  A pointer to the global object. Provided for quick
 //                access to the global object from inside the code (since
@@ -429,9 +428,6 @@ class Context: public FixedArray {
   ScopeInfo* scope_info();
   String* catch_name();
 
-  inline JSModule* module();
-  inline void set_module(JSModule* module);
-
   // Get the context where var declarations will be hoisted to, which
   // may be the context itself.
   Context* declaration_context();