Intermittent crash in /html/semantics/scripting-1/the-script-element/module/errorhandling.html

[jdm]

1 unexpected results that are NOT known-intermittents:
  ▶ CRASH [expected OK] /html/semantics/scripting-1/the-script-element/module/errorhandling.html
  │ 
  │ 
  │ 
  │ 
  │ [2020-01-08T12:12:08Z ERROR script::script_module] Failed to fetch http://web-platform.test:8000/html/semantics/scripting-1/the-script-element/module/errorhandling-wrongMimetype.js?pipe=header(Content-Type,text/plain) with error Internal("Invalid MIME type: text/plain")
  │ [2020-01-08T12:12:08Z ERROR script::dom::bindings::error] Error at http://web-platform.test:8000/html/semantics/scripting-1/the-script-element/module/errorhandling-parseerror-root.html:4:9 identifier starts immediately after numeric literal
  │ [2020-01-08T12:12:08Z ERROR script::dom::bindings::error] Error at http://web-platform.test:8000/html/semantics/scripting-1/the-script-element/module/errorhandling-parseerror-dependent.js:2:1 identifier starts immediately after numeric literal
  │ Stack trace for thread "ScriptThread PipelineId { namespace_id: PipelineNamespaceId(1), index: PipelineIndex(1) }"
  │ stack backtrace:
  │    0: servo::backtrace::print
  │    1: servo::install_crash_handler::handler
  │    2: _ZL15WasmTrapHandleriP9siginfo_tPv
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/wasm/WasmSignalHandlers.cpp:969
  │    3: <unknown>
  │    4: _ZL9MOZ_CrashPKciS0_
  │              at /repo/target/release/build/mozjs_sys-507f23220221d5ed/out/dist/include/mozilla/Assertions.h:314
  │    5: MOZ_CrashPrintf
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/mfbt/Assertions.cpp:55
  │    6: _ZN2js13ContextChecks4failEPN2JS11CompartmentES3_i
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:43
  │       _ZN2js13ContextChecks5checkEPN2JS11CompartmentEi
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:59
  │       _ZN2js13ContextChecks5checkEP8JSObjecti
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:73
  │       _ZN2js13ContextChecks5checkERKN2JS5ValueEi
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:110
  │    7: _ZN9JSContext9checkImplIN2JS6HandleINS1_5ValueEEEJEEEviRKT_DpRKT0_
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:184
  │       _ZN9JSContext12releaseCheckIJN2JS6HandleINS1_5ValueEEEEEEvDpRKT_
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/vm/JSContext-inl.h:200
  │       _Z22JS_SetPendingExceptionP9JSContextN2JS6HandleINS1_5ValueEEE
  │              at /root/.cargo/git/checkouts/mozjs-fa11ffc7d4f1cc2d/5906588/mozjs/js/src/jsapi.cpp:5169
  │    8: script::script_module::ModuleTree::report_error
  │    9: script::dom::htmlscriptelement::HTMLScriptElement::run_a_module_script
  │   10: script::dom::htmlscriptelement::HTMLScriptElement::execute
  │   11: _ZN6script3dom8document8Document24process_deferred_scripts17h11ee5aee1c4c8b40E.llvm.7929975889279222091
  │   12: script::dom::document::Document::finish_load
  │   13: script::dom::servoparser::ServoParser::do_parse_sync
  │   14: profile_traits::time::profile
  │   15: _ZN6script3dom11servoparser11ServoParser10parse_sync17h761ec7d65ff00b33E.llvm.12672534926458395703
  │   16: <script::dom::servoparser::ParserContext as net_traits::FetchResponseListener>::process_response_eof
  │   17: script::script_thread::ScriptThread::handle_msg_from_constellation
  │   18: _ZN6script13script_thread12ScriptThread11handle_msgs17hbad02c22c093deabE.llvm.7929975889279222091
  │   19: script::script_thread::ScriptThread::start
  │   20: profile_traits::mem::ProfilerChan::run_with_memory_reporting
  │   21: std::sys_common::backtrace::__rust_begin_short_backtrace
  │   22: _ZN3std9panicking3try7do_call17hbe80c412e598cb91E.llvm.11320686548051288937
  │   23: __rust_maybe_catch_panic
  │              at src/libpanic_unwind/lib.rs:78
  │   24: core::ops::function::FnOnce::call_once{{vtable.shim}}
  │   25: <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once
  │              at /rustc/9b98af84c4aa66392236fff59c86da2130d46d46/src/liballoc/boxed.rs:1022
  │   26: <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once
  │              at /rustc/9b98af84c4aa66392236fff59c86da2130d46d46/src/liballoc/boxed.rs:1022
  │       std::sys_common::thread::start_thread
  │              at src/libstd/sys_common/thread.rs:13
  │       std::sys::unix::thread::Thread::new::thread_start
  │              at src/libstd/sys/unix/thread.rs:80
  │   27: start_thread
  │   28: __clone

I suspect we need to enter a realm.