perf(ext/web): optimize timer cancellation (#16316)

Towards #16315 

It created a bunch of Error objects and rejected the promise. This patch
changes `op_sleep` to resolve with `true` if it was cancelled.

1 files changed, 6 insertions, 4 deletions

diff --git a/ext/web/timers.rs b/ext/web/timers.rs
index ba5e12d62..5b1310792 100644
--- a/ext/web/timers.rs
+++ b/ext/web/timers.rs
@@ -77,15 +77,17 @@ pub fn op_timer_handle(state: &mut OpState) -> ResourceId {
 
 /// Waits asynchronously until either `millis` milliseconds have passed or the
 /// [`TimerHandle`] resource given by `rid` has been canceled.
+///
+/// If the timer is canceled, this returns `false`. Otherwise, it returns `true`.
 #[op(deferred)]
 pub async fn op_sleep(
   state: Rc<RefCell<OpState>>,
   millis: u64,
   rid: ResourceId,
-) -> Result<(), AnyError> {
+) -> Result<bool, AnyError> {
   let handle = state.borrow().resource_table.get::<TimerHandle>(rid)?;
-  tokio::time::sleep(Duration::from_millis(millis))
+  let res = tokio::time::sleep(Duration::from_millis(millis))
     .or_cancel(handle.0.clone())
-    .await?;
-  Ok(())
+    .await;
+  Ok(res.is_ok())
 }