[IMP] env: env is now frozen, useSubEnv does not affect user env

src/app/app.ts

@@ -6,9 +6,13 @@ import { TemplateSet } from "./template_set";
 
 // reimplement dev mode stuff see last change in 0f7a8289a6fb8387c3c1af41c6664b2a8448758f
 
+export interface Env {
+  [key: string]: any;
+}
+
 interface Config {
   dev?: boolean;
-  env?: { [key: string]: any };
+  env?: Env;
   translatableAttributes?: string[];
   translateFn?: (s: string) => string;
 }
@@ -21,7 +25,7 @@ See https://github.com/odoo/owl/blob/master/doc/reference/config.md#mode for mor
 export class App<T extends typeof Component = any> extends TemplateSet {
   Root: T;
   props: any;
-  env: any = {};
+  env: Env = Object.freeze({});
   scheduler = new Scheduler(window.requestAnimationFrame.bind(window));
   root: ComponentNode | null = null;
 
@@ -36,9 +40,8 @@ export class App<T extends typeof Component = any> extends TemplateSet {
       this.dev = config.dev;
       console.info(DEV_MSG);
     }
-
     if (config.env) {
-      this.env = config.env;
+      this.env = Object.freeze(Object.assign({}, config.env));
     }
     if (config.translateFn) {
       this.translateFn = config.translateFn;