Auto merge of #15029 - aneeshusa:check-whole-constellation-for-panics, r=asajeffrey

Check all constellation files for panics

Teaches the `etc/ci/check_no_panic.sh` script to handle directories,
so it can check all constellation files for panics.

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r? @asajeffrey
There are currently 4 `unwrap()`s in `components/constellation/timer_scheduler.rs`; I'm not sure how you want to handle those.

---
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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #14976 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because it adds more testing coverage

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components/constellation/timer_scheduler.rs

@@ -39,7 +39,7 @@ impl PartialEq for ScheduledEvent {
 
 impl TimerScheduler {
     pub fn start() -> IpcSender<TimerEventRequest> {
-        let (req_ipc_sender, req_ipc_receiver) = ipc::channel().unwrap();
+        let (req_ipc_sender, req_ipc_receiver) = ipc::channel().expect("Channel creation failed.");
         let (req_sender, req_receiver) = mpsc::sync_channel(1);
 
         // We could do this much more directly with recv_timeout
@@ -92,7 +92,7 @@ impl TimerScheduler {
                 // This thread can terminate if the req_ipc_sender is dropped.
                 warn!("TimerScheduler thread terminated.");
             })
-            .unwrap()
+            .expect("Thread creation failed.")
             .thread()
             .clone();
 
@@ -105,13 +105,13 @@ impl TimerScheduler {
             .name(String::from("TimerProxy"))
             .spawn(move || {
                 while let Ok(req) = req_ipc_receiver.recv() {
-                    req_sender.send(req).unwrap();
+                    let _ = req_sender.send(req);
                     timeout_thread.unpark();
                 }
                 // This thread can terminate if the req_ipc_sender is dropped.
                 warn!("TimerProxy thread terminated.");
             })
-            .unwrap();
+            .expect("Thread creation failed.");
 
         // Return the IPC sender
         req_ipc_sender