Move debug check to runtime_debug.js. NFC (#22659)

Author: sbc100

src/runtime_debug.js

@@ -16,6 +16,10 @@
 })();
 #endif
 
+if (Module['ENVIRONMENT']) {
+  throw new Error('Module.ENVIRONMENT has been deprecated. To force the environment, use the ENVIRONMENT compile-time option (for example, -sENVIRONMENT=web or -sENVIRONMENT=node)');
+}
+
 function legacyModuleProp(prop, newName, incoming=true) {
   if (!Object.getOwnPropertyDescriptor(Module, prop)) {
     Object.defineProperty(Module, prop, {

src/shell.js

@@ -104,12 +104,6 @@ var ENVIRONMENT_IS_SHELL = !ENVIRONMENT_IS_WEB && !ENVIRONMENT_IS_NODE && !ENVIR
 #endif
 #endif // ENVIRONMENT
 
-#if ASSERTIONS
-if (Module['ENVIRONMENT']) {
-  throw new Error('Module.ENVIRONMENT has been deprecated. To force the environment, use the ENVIRONMENT compile-time option (for example, -sENVIRONMENT=web or -sENVIRONMENT=node)');
-}
-#endif
-
 #if PTHREADS
 // Three configurations we can be running in:
 // 1) We could be the application main() thread running in the main JS UI thread. (ENVIRONMENT_IS_WORKER == false and ENVIRONMENT_IS_PTHREAD == false)