### Preflight Checklist

- [X] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
- [X] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
- [X] I have searched the [issue tracker](https://www.github.com/electron/electron/issues) for a feature request that matches the one I want to file, without success.

### Electron Version

12.0.1

### What operating system are you using?

macOS

### Operating System Version

11.2

### What arch are you using?

x64

### Last Known Working Electron version

_No response_

### Expected Behavior

`error.message` shouldn't be prefixed with "Uncaught Error:"

### Actual Behavior

`error.message` is prefixed with "Uncaught Error:" when an error is thrown in a function defined in the preload script and caught in the renderer process. This only happens when `contextIsolation` is enabled.

### Testcase Gist URL

https://gist.github.com/f11c77f9bc2cbf98d42a9fcaf477c80a


shell/renderer/api/electron_api_context_bridge.cc
return v8::MaybeLocal<v8::Value>(value);
  }
  
  auto cached_value = object_cache->GetCachedProxiedObject(value);
  if (!cached_value.IsEmpty()) {
    return cached_value;
  }
  
  
  if (value->IsFunction()) {
    auto func = v8::Local<v8::Function>::Cast(value);
    v8::MaybeLocal<v8::Value> maybe_original_fn = GetPrivate(
        source_context, func, context_bridge::kOriginalFunctionPrivateKey);
    {
      v8::Context::Scope destination_scope(destination_context);
      v8::Local<v8::Value> proxy_func;
      
      
      
      
      
      
      if (maybe_original_fn.ToLocal(&proxy_func) && proxy_func->IsFunction() &&
          proxy_func.As<v8::Object>()->CreationContext() ==
              destination_context) {
        return v8::MaybeLocal<v8::Value>(proxy_func);
      }
      v8::Local<v8::Object> state =
          v8::Object::New(destination_context->GetIsolate());
      SetPrivate(destination_context, state,