chore(core): Split JsRuntimeForSnapshot from JsRuntime (#19308)

This cleans up `JsRuntime` a bit more:

* We no longer print cargo's rerun-if-changed messages in `JsRuntime` --
those are printed elsewhere
* We no longer special case the OwnedIsolate for snapshots. Instead we
make use of an inner object that has the `Drop` impl and allows us to
`std::mem::forget` it if we need to extract the isolate for a snapshot
* The `snapshot` method is only available on `JsRuntimeForSnapshot`, not
`JsRuntime`.
* `OpState` construction is slightly cleaner, though I'd still like to
extract more

---------

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

1 files changed, 4 insertions, 1 deletions

diff --git a/runtime/build.rs b/runtime/build.rs
index 334c3b11a..f656682a1 100644
--- a/runtime/build.rs
+++ b/runtime/build.rs
@@ -337,7 +337,7 @@ mod startup_snapshot {
       runtime_main::init_ops_and_esm(),
     ];
 
-    create_snapshot(CreateSnapshotOptions {
+    let output = create_snapshot(CreateSnapshotOptions {
       cargo_manifest_dir: env!("CARGO_MANIFEST_DIR"),
       snapshot_path,
       startup_snapshot: None,
@@ -345,6 +345,9 @@ mod startup_snapshot {
       compression_cb: None,
       snapshot_module_load_cb: Some(Box::new(transpile_ts_for_snapshotting)),
     });
+    for path in output.files_loaded_during_snapshot {
+      println!("cargo:rerun-if-changed={}", path.display());
+    }
   }
 }