Auto merge of #13755 - fhartwig:early-return, r=KiChjang

Invert conditional and return early from report_pending_exception

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Previously, almost the entire body of `report_pending_exception` was in a conditional branch. We now return early if the function body does not need to be executed.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #13746 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because they don't add any new functionality.

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components/script/dom/bindings/error.rs

@@ -202,7 +202,8 @@ impl ErrorInfo {
 /// The `dispatch_event` argument is temporary and non-standard; passing false
 /// prevents dispatching the `error` event.
 pub unsafe fn report_pending_exception(cx: *mut JSContext, dispatch_event: bool) {
-    if JS_IsExceptionPending(cx) {
+    if !JS_IsExceptionPending(cx) { return; }
+
     rooted!(in(cx) let mut value = UndefinedValue());
     if !JS_GetPendingException(cx, value.handle_mut()) {
         JS_ClearPendingException(cx);
@@ -248,7 +249,6 @@ pub unsafe fn report_pending_exception(cx: *mut JSContext, dispatch_event: bool)
         GlobalScope::from_context(cx)
             .report_an_error(error_info, value.handle());
     }
-    }
 }
 
 /// Throw an exception to signal that a `JSVal` can not be converted to any of