* Electron version: 1.6.15
* Operating system: Linux

### Expected behavior

Open a `BrowserWindow` with passed options

### Actual behavior

  - Usually a Segmentation fault.
  - Sometimes `[12843:0100/000000.043847:FATAL:zygote_linux.cc(479)] Failed to synchronise with parent zygote process`
  - Sometimes `[12819:0100/000000.719122:FATAL:zygote_linux.cc(509)] Check failed: len > 0 (0 vs. 0)`

### How to reproduce

I'm still working on making a smaller reproduction case. The issue goes away with small tweaks.

1. Starting from https://github.com/daurnimator/fengari-electron-example
2. Modify main.lua to contain:
```lua
local js = require "js"
local electron = require "electron"

electron.app:on("ready", function()
	local win = js.new(electron.BrowserWindow, js.createproxy({
		backgroundColor = '#2e2c29';
	}, "object"))
	win:loadURL("https://fengari.io")
end)
```

atom/browser/api/atom_api_web_contents.cc
web_contents()->FocusThroughTabTraversal(reverse);
}
bool WebContents::SendIPCMessage(bool all_frames,
                                 const base::string16& channel,
                                 const base::ListValue& args) {
  return Send(new AtomViewMsg_Message(routing_id(), all_frames, channel, args));
}
void WebContents::SendInputEvent(v8::Isolate* isolate,
                                 v8::Local<v8::Value> input_event) {
  const auto view = static_cast<content::RenderWidgetHostViewBase*>(
    web_contents()->GetRenderWidgetHostView());
  if (!view)
    return;
  blink::WebInputEvent::Type type = mate::GetWebInputEventType(isolate,
      input_event);
  if (blink::WebInputEvent::IsMouseEventType(type)) {
    blink::WebMouseEvent mouse_event;
    if (mate::ConvertFromV8(isolate, input_event, &mouse_event)) {
      view->ProcessMouseEvent(mouse_event, ui::LatencyInfo());
      return;
    }
  } else if (blink::WebInputEvent::IsKeyboardEventType(type)) {
    content::NativeWebKeyboardEvent keyboard_event(
        blink::WebKeyboardEvent::kRawKeyDown,
        blink::WebInputEvent::kNoModifiers,
        ui::EventTimeForNow());