refactor: Use ES modules for internal runtime code (#17648)

This PR refactors all internal js files (except core) to be written as
ES modules.
`__bootstrap`has been mostly replaced with static imports in form in
`internal:[path to file from repo root]`.
To specify if files are ESM, an `esm` method has been added to
`Extension`, similar to the `js` method.
A new ModuleLoader called `InternalModuleLoader` has been added to
enable the loading of internal specifiers, which is used in all
situations except when a snapshot is only loaded, and not a new one is
created from it.

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 11 insertions, 16 deletions

diff --git a/runtime/js/40_diagnostics.js b/runtime/js/40_diagnostics.js
index 6939b5204..669a54263 100644
--- a/runtime/js/40_diagnostics.js
+++ b/runtime/js/40_diagnostics.js
@@ -3,22 +3,17 @@
 // Diagnostic provides an abstraction for advice/errors received from a
 // compiler, which is strongly influenced by the format of TypeScript
 // diagnostics.
-"use strict";
 
-((window) => {
-  const DiagnosticCategory = {
-    0: "Warning",
-    1: "Error",
-    2: "Suggestion",
-    3: "Message",
+const DiagnosticCategory = {
+  0: "Warning",
+  1: "Error",
+  2: "Suggestion",
+  3: "Message",
 
-    Warning: 0,
-    Error: 1,
-    Suggestion: 2,
-    Message: 3,
-  };
+  Warning: 0,
+  Error: 1,
+  Suggestion: 2,
+  Message: 3,
+};
 
-  window.__bootstrap.diagnostics = {
-    DiagnosticCategory,
-  };
-})(this);
+export { DiagnosticCategory };