Auto merge of #13406 - Mylainos:issue-13377, r=jdm

Extract panic-catching for JS engine callbacks into a separate function

All of our generated code for script contains inline code like this:
```
let result = panic::catch_unwind(AssertUnwindSafe(|| {
    ...
};
match result {
    Ok(result) => result,
    Err(error) => {
        store_panic_result(error);
        return false;
    }
}
```
This PR change it to something like this:
```
wrap_panic(|| { ... }, false)
```

---
- [X] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [X] These changes fix #13377

- [ ] There are tests for these changes

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1 files changed, 15 insertions, 0 deletions

diff --git a/components/script/dom/bindings/utils.rs b/components/script/dom/bindings/utils.rs
index 32ffe4109ae..4a7d4d698fb 100644
--- a/components/script/dom/bindings/utils.rs
+++ b/components/script/dom/bindings/utils.rs
@@ -32,8 +32,11 @@ use js::jsapi::{JS_StringHasLatin1Chars, MutableHandleValue, ObjectOpResult};
 use js::jsval::{JSVal, UndefinedValue};
 use js::rust::{GCMethods, ToString};
 use libc;
+use script_runtime::store_panic_result;
 use std::ffi::CString;
 use std::os::raw::c_void;
+use std::panic;
+use std::panic::AssertUnwindSafe;
 use std::ptr;
 use std::slice;
 
@@ -513,3 +516,15 @@ unsafe extern "C" fn instance_class_has_proto_at_depth(clasp: *const js::jsapi::
 pub const DOM_CALLBACKS: DOMCallbacks = DOMCallbacks {
     instanceClassMatchesProto: Some(instance_class_has_proto_at_depth),
 };
+
+/// Generic wrapper for JS engine callbacks panic-catching
+pub fn wrap_panic<T: FnMut() -> R, R>(function: T, generic_return_type: R) -> R {
+    let result = panic::catch_unwind(AssertUnwindSafe(function));
+    match result {
+        Ok(result) => result,
+        Err(error) => {
+            store_panic_result(error);
+            generic_return_type
+        }
+    }
+}