* 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
content::WebContents* web_contents,
    bool user_gesture,
    bool last_unlocked_by_target) {
  auto permission_helper =
      WebContentsPermissionHelper::FromWebContents(web_contents);
  permission_helper->RequestPointerLockPermission(user_gesture);
}
std::unique_ptr<content::BluetoothChooser> WebContents::RunBluetoothChooser(
    content::RenderFrameHost* frame,
    const content::BluetoothChooser::EventHandler& event_handler) {
  std::unique_ptr<BluetoothChooser> bluetooth_chooser(
      new BluetoothChooser(this, event_handler));
  return std::move(bluetooth_chooser);
}
content::JavaScriptDialogManager*
WebContents::GetJavaScriptDialogManager(
    content::WebContents* source) {
  if (!dialog_manager_)
    dialog_manager_.reset(new AtomJavaScriptDialogManager(this));
  return dialog_manager_.get();
}
void WebContents::BeforeUnloadFired(const base::TimeTicks& proceed_time) {
  
  
}
void WebContents::RenderViewCreated(content::RenderViewHost* render_view_host) {