[wasm] Allocate a single script per wasm module

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 6c189947a7b17abd52a1c503a810e9c0c764532e..baf579d4f72c51ee2d03d10ecca33bd1349db66b 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7054,13 +7054,9 @@ class Script: public Struct {
   // [source_mapping_url]: sourceMappingURL magic comment
   DECL_ACCESSORS(source_mapping_url, Object)
 
-  // [wasm_instance]: the wasm instance this script belongs to.
+  // [wasm_compiled_module]: the compiled wasm module this script belongs to.
   // This must only be called if the type of this script is TYPE_WASM.
-  DECL_ACCESSORS(wasm_instance, JSObject)
-
-  // [wasm_function_index]: the wasm function index this script belongs to.
-  // This must only be called if the type of this script is TYPE_WASM.
-  DECL_INT_ACCESSORS(wasm_function_index)
+  DECL_ACCESSORS(wasm_compiled_module, Object)
 
   // [compilation_type]: how the the script was compiled. Encoded in the
   // 'flags' field.