[wasm] Use a Managed<WasmModule> to hold metadata about modules.

src/snapshot/code-serializer.h

Index: src/snapshot/code-serializer.h
diff --git a/src/snapshot/code-serializer.h b/src/snapshot/code-serializer.h
index 6577df8c855cc0f1ff8d4c4b4c118222b4a7fc01..b9fc3608f31773b33462a8da572a68a3e5b94068 100644
--- a/src/snapshot/code-serializer.h
+++ b/src/snapshot/code-serializer.h
@@ -74,7 +74,9 @@ class WasmCompiledModuleSerializer : public CodeSerializer {
     }
   }
 
-  bool ElideObject(Object* obj) override { return obj->IsWeakCell(); };
+  bool ElideObject(Object* obj) override {
+    return obj->IsWeakCell() || obj->IsForeign();
+  };
 
  private:
   WasmCompiledModuleSerializer(Isolate* isolate, uint32_t source_hash)