Invalid Rust closure invocation from JavaScript: Improve error message

[ActuallyHappening]

Describe the Bug

Pass a Rust closure into the JavaScript world that takes a String (haven't tested &str) and invoke the Rust closure with a JavaScript object (e.g. {}).
You will get a very annoying error that doesn't describe what you did at all: [Error] RuntimeError: Unreachable code should not be executed (evaluating 'realloc(ptr, len, len = offset + arg.length * 3)')
This is not a bug, however the error message can be improved

Steps to Reproduce

From Rust side, put a closure into the 'global' or window scope:

#[wasm_bindgen(inline_js="export func register(f) {window._func=f}")]
extern "C" {
	fn register(f: &Closure<dyn FnMut(String)>);
}

Then register it:

register(&Closure::new(move |_| {
    //info!("RS: Closure called");
}));

From the JS side, load a script into the HTML and execute it, calling window._func with a JS Object (not the expected String):

//console.log("JS: Calling _func");
window._func({});

Expected Behavior

An error should occur, since the Rust closure was invoked with the wrong arguments.
I would like a clear and concise error message of what wasm-bindgen expected to happen compared to what did happen.
Maybe an error message like Did you call a Rust closure with invalid arguments? instead of RuntimeError: Unreachable code should not be executed (evaluating 'realloc(ptr, len, len = offset + arg.length * 3)'

Actual Behaviour

This error message was logged using the console_error_panic_hook crate running on Safari (using leptos to insert JS script, and calling from a JS firebase callback fn), although my error seems generic (but I haven't tested it on other platforms).

[Error] panicked at 'assertion failed: old_size > 0', /Users/____/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasm-bindgen-0.2.84/src/lib.rs:1582:13

Stack:

@http://localhost:3000/pkg/leptos_start.js:319:22
wasm-stub@[wasm code]
<?>.wasm-function[console_error_panic_hook::Error::new::h6003d8e0d95f40a6]@[wasm code]
<?>.wasm-function[console_error_panic_hook::hook_impl::hed4b238597fbcbc2]@[wasm code]
<?>.wasm-function[console_error_panic_hook::hook::h234aaf9173a64a91]@[wasm code]
<?>.wasm-function[core::ops::function::Fn::call::hdd0a65b357887f78]@[wasm code]
<?>.wasm-function[std::panicking::rust_panic_with_hook::h053fef1466f0a872]@[wasm code]
<?>.wasm-function[std::panicking::begin_panic_handler::{{closure}}::hc1e7cbf0244868f5]@[wasm code]
<?>.wasm-function[std::sys_common::backtrace::__rust_end_short_backtrace::h5e48744231590951]@[wasm code]
<?>.wasm-function[rust_begin_unwind]@[wasm code]
<?>.wasm-function[core::panicking::panic_fmt::h527018da77170278]@[wasm code]
<?>.wasm-function[core::panicking::panic::h0baae8c244a97243]@[wasm code]
<?>.wasm-function[__wbindgen_realloc]@[wasm code]
wasm-stub@[wasm code]
1225@[native code]
passStringToWasm0@http://localhost:3000/pkg/leptos_start.js:128:34
__wbg_adapter_38@http://localhost:3000/pkg/leptos_start.js:229:31
real@http://localhost:3000/pkg/leptos_start.js:214:33
emit_event@http://localhost:3000/bundle.js:15238:16
@http://localhost:3000/bundle.js:15291:23
@http://localhost:3000/bundle.js:15267:17
onValue@http://localhost:3000/bundle.js:14503:39
exceptionGuard@http://localhost:3000/bundle.js:3824:15
eventListRaise@http://localhost:3000/bundle.js:13622:31
eventQueueRaiseQueuedEventsMatchingPredicate@http://localhost:3000/bundle.js:13597:35
eventQueueRaiseEventsForChangedPath@http://localhost:3000/bundle.js:13586:53
repoOnDataUpdate@http://localhost:3000/bundle.js:13804:44
@http://localhost:3000/bundle.js:13703:33
onDataPush_@http://localhost:3000/bundle.js:6756:35
onDataMessage_@http://localhost:3000/bundle.js:6750:33
onDataMessage_@[native code]
onDataMessage_@http://localhost:3000/bundle.js:5596:28
onPrimaryMessageReceived_@http://localhost:3000/bundle.js:5590:36
@http://localhost:3000/bundle.js:5492:55
appendFrame_@http://localhost:3000/bundle.js:5109:31
handleIncomingFrame@http://localhost:3000/bundle.js:5157:38
@http://localhost:3000/bundle.js:5056:41


	(anonymous function) (leptos_start.js:316)
	wasm-stub
	<?>.wasm-function[console_error_panic_hook::error::h729d7e127797de6e]
	<?>.wasm-function[console_error_panic_hook::hook_impl::hed4b238597fbcbc2]
	<?>.wasm-function[console_error_panic_hook::hook::h234aaf9173a64a91]
	<?>.wasm-function[core::ops::function::Fn::call::hdd0a65b357887f78]
	<?>.wasm-function[std::panicking::rust_panic_with_hook::h053fef1466f0a872]
	<?>.wasm-function[std::panicking::begin_panic_handler::{{closure}}::hc1e7cbf0244868f5]
	<?>.wasm-function[std::sys_common::backtrace::__rust_end_short_backtrace::h5e48744231590951]
	<?>.wasm-function[rust_begin_unwind]
	<?>.wasm-function[core::panicking::panic_fmt::h527018da77170278]
	<?>.wasm-function[core::panicking::panic::h0baae8c244a97243]
	<?>.wasm-function[__wbindgen_realloc]
	wasm-stub
	1225
	passStringToWasm0 (leptos_start.js:128)
	__wbg_adapter_38 (leptos_start.js:229)
	real (leptos_start.js:214)
	emit_event (bundle.js:15238)
	(anonymous function) (bundle.js:15291)
	(anonymous function) (bundle.js:15267)
	onValue (bundle.js:14503)
	exceptionGuard (bundle.js:3824)
	eventListRaise (bundle.js:13622)
	eventQueueRaiseQueuedEventsMatchingPredicate (bundle.js:13597)
	eventQueueRaiseEventsForChangedPath (bundle.js:13586)
	repoOnDataUpdate (bundle.js:13804)
	(anonymous function) (bundle.js:13703)
	onDataPush_ (bundle.js:6756)
	onDataMessage_ (bundle.js:6750)
	onDataMessage_
	onDataMessage_ (bundle.js:5596)
	onPrimaryMessageReceived_ (bundle.js:5590)
	(anonymous function) (bundle.js:5492)
	appendFrame_ (bundle.js:5109)
	handleIncomingFrame (bundle.js:5157)
	(anonymous function) (bundle.js:5056)

This error also happened (full stack omitted):

[Error] RuntimeError: Unreachable code should not be executed (evaluating 'realloc(ptr, len, len = offset + arg.length * 3)')

	(anonymous function) (bundle.js:3835)

Additional Context

Using Safari, happy to add any more details upon request