* Electron version: 2.0.0-beta.4
* Operating system: macOS 10.13.3

### Expected behavior

A reload of the window works.

### Actual behavior

A reload of the window does not work.

### How to reproduce

* run VSCode exploration ([download](https://az764295.vo.msecnd.net/exploration/6bc3274250cc949c7fb1d654cbb6e59c8ddad697/VSCode-darwin-exploration.zip))
* run "Reload Window" command
* sometimes I see the window stay blank after doing so and checking the console I see:

```
Uncaught (in promise) Error: Cannot get property 'id' on missing remote object 3
Error: Cannot get property 'id' on missing remote object 3
    at throwRPCError (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/rpc-server.js:143:17)
    at EventEmitter.<anonymous> (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/rpc-server.js:384:7)
    at emitThree (events.js:136:13)
    at EventEmitter.emit (events.js:217:7)
    at WebContents.<anonymous> (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/api/web-contents.js:295:13)
    at emitTwo (events.js:126:13)
    at WebContents.emit (events.js:214:7)
    at throwRPCError (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/rpc-server.js:143:17)
    at EventEmitter.<anonymous> (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/rpc-server.js:384:7)
    at emitThree (events.js:136:13)
    at EventEmitter.emit (events.js:217:7)
    at WebContents.<anonymous> (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/browser/api/web-contents.js:295:13)
    at emitTwo (events.js:126:13)
    at WebContents.emit (events.js:214:7)
    at Object.exception (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/renderer/api/remote.js:209:30)
    at metaToValue (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/renderer/api/remote.js:213:28)
    at Object.descriptor.get [as id] (/Applications/Visual Studio Code - Exploration.app/Contents/Resources/electron.asar/renderer/api/remote.js:132:16)
    at file:///Applications/Visual%20Studio%20Code%20-%20Exploration.app/Contents/Resources/app/out/vs/workbench/electron-browser/bootstrap/index.js:11:97
    at new Promise (<anonymous>)
    at file:///Applications/Visual%20Studio%20Code%20-%20Exploration.app/Contents/Resources/app/out/vs/workbench/electron-browser/bootstrap/index.js:10:838
```
atom/common/options_switches.cc
const char kTabbingIdentifier[] = "tabbingIdentifier";
const char kAutoHideMenuBar[] = "autoHideMenuBar";
const char kEnableLargerThanScreen[] = "enableLargerThanScreen";
const char kDarkTheme[] = "darkTheme";
const char kTransparent[] = "transparent";
const char kType[] = "type";
const char kDisableAutoHideCursor[] = "disableAutoHideCursor";
const char kStandardWindow[] = "standardWindow";
const char kBackgroundColor[] = "backgroundColor";
const char kHasShadow[] = "hasShadow";
const char kOpacity[] = "opacity";
const char kFocusable[] = "focusable";
const char kWebPreferences[] = "webPreferences";
const char kVibrancyType[] = "vibrancy";
const char kZoomFactor[] = "zoomFactor";
const char kPreloadScript[] = "preload";
const char kPreloadURL[] = "preloadURL";
const char kNodeIntegration[] = "nodeIntegration";
const char kContextIsolation[] = "contextIsolation";
const char kGuestInstanceID[] = "guestInstanceId";
const char kExperimentalFeatures[]       = "experimentalFeatures";
const char kExperimentalCanvasFeatures[] = "experimentalCanvasFeatures";
const char kOpenerID[] = "openerId";
const char kScrollBounce[] = "scrollBounce";
const char kBlinkFeatures[] = "blinkFeatures";
const char kDisableBlinkFeatures[] = "disableBlinkFeatures";
const char kNodeIntegrationInWorker[] = "nodeIntegrationInWorker";
const char kWebviewTag[] = "webviewTag";
const char kCustomArgs[] = "additionalArguments";
}