* Output of `node_modules/.bin/electron --version`: v3.0.0-beta.8
* Operating System (Platform and Version): Windows 10 10.0.16299 Build 16299
* Output of `node_modules/.bin/electron --version` on last known working Electron version (if applicable): v2.0.8

**Expected Behavior**
Webview DevTools should open in a window that is properly sized.

**Actual behavior**
Webview DevTools open in window with minimal size and are therefore not visible.

**To Reproduce**
**Edit** Works in BrowserWindow.webContents.openDevTools() Works **not** in webView.openDevTools()

**Screenshots**
![too_small_devtools_window](https://user-images.githubusercontent.com/6893212/44841398-850fed80-ac43-11e8-8bed-849d45473683.png)

**Additional Information**
Only reproducible on Windows 10 10.0.16299 Build 16299. Works correctly on MacOS High Sierra 10.13.4

brightray/browser/inspectable_web_contents_impl.cc
return devtools_bounds_;
}
void InspectableWebContentsImpl::SaveDevToolsBounds(const gfx::Rect& bounds) {
  base::DictionaryValue bounds_dict;
  RectToDictionary(bounds, &bounds_dict);
  pref_service_->Set(kDevToolsBoundsPref, bounds_dict);
  devtools_bounds_ = bounds;
}
double InspectableWebContentsImpl::GetDevToolsZoomLevel() const {
  return pref_service_->GetDouble(kDevToolsZoomPref);
}
void InspectableWebContentsImpl::UpdateDevToolsZoomLevel(double level) {
  pref_service_->SetDouble(kDevToolsZoomPref, level);
}
void InspectableWebContentsImpl::ActivateWindow() {
  
  SetZoomLevelForWebContents(GetDevToolsWebContents(), GetDevToolsZoomLevel());
}
void InspectableWebContentsImpl::CloseWindow() {
  GetDevToolsWebContents()->DispatchBeforeUnload();
}
void InspectableWebContentsImpl::LoadCompleted() {