script: Propagate a pending JS exception on structured cloning (#37964)

During the object (de)serialization steps on structured cloning
https://html.spec.whatwg.org/multipage/#safe-passing-of-structured-data
it is possible to throw a JS exception.

`self.postMessage({ get whatever() { throw customError } }));`

Require to propagate a pending JS exception and not throw the default
"DataCloneError" DOM exception.

Testing: Improvements in the following tests
- html/infrastructure/safe-passing-of-structured-data/*
- html/webappapis/structured-clone/structured-clone.any.js*
- wasm/serialization/arraybuffer/transfer.window.js
- webmessaging/without-ports/026.html
- workers/semantics/structured-clone/dedicated.html

Signed-off-by: Andrei Volykhin <andrei.volykhin@gmail.com>

components/script/dom/bindings/structuredclone.rs

@@ -24,7 +24,7 @@ use js::glue::{
     NewJSAutoStructuredCloneBuffer, WriteBytesToJSStructuredCloneData,
 };
 use js::jsapi::{
-    CloneDataPolicy, HandleObject as RawHandleObject, Heap, JS_ClearPendingException,
+    CloneDataPolicy, HandleObject as RawHandleObject, Heap, JS_IsExceptionPending,
     JS_ReadUint32Pair, JS_STRUCTURED_CLONE_VERSION, JS_WriteUint32Pair, JSContext, JSObject,
     JSStructuredCloneCallbacks, JSStructuredCloneReader, JSStructuredCloneWriter,
     MutableHandleObject as RawMutableHandleObject, StructuredCloneScope, TransferableOwnership,
@@ -619,8 +619,13 @@ pub(crate) fn write(
             val.handle(),
         );
         if !result {
-            JS_ClearPendingException(*cx);
-            return Err(sc_writer.error.unwrap_or(Error::DataClone(None)));
+            let error = if JS_IsExceptionPending(*cx) {
+                Error::JSFailed
+            } else {
+                sc_writer.error.unwrap_or(Error::DataClone(None))
+            };
+
+            return Err(error);
         }
 
         let nbytes = GetLengthOfJSStructuredCloneData(scdata);
@@ -696,8 +701,13 @@ pub(crate) fn read(
             sc_reader_ptr as *mut raw::c_void,
         );
         if !result {
-            JS_ClearPendingException(*cx);
-            return Err(sc_reader.error.unwrap_or(Error::DataClone(None)));
+            let error = if JS_IsExceptionPending(*cx) {
+                Error::JSFailed
+            } else {
+                sc_reader.error.unwrap_or(Error::DataClone(None))
+            };
+
+            return Err(error);
         }
 
         DeleteJSAutoStructuredCloneBuffer(scbuf);