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# Description

* Electron version: 1.8.4
* Operating system: Windows 10

Calling `webContents.sendInputEvent` with type as `"char"` to a document containing a webview is rendered offscreen and an input panel is focused

<!-- What do you think should happen? -->

# Expected result

Keyboard input should be placed into the input panel

<!-- What actually happens? -->

# Actual result

Electron crashes

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# Repro steps

[I have a repo set up that will demonstrate the issue.](https://github.com/ImOnALampshade/electron-webview-char-crash) Clone that to see. Read the readme in that for more information.

```bash
git clone https://github.com/ImOnALampshade/electron-webview-char-crash.git
npm install
npm start
```
atom/browser/api/atom_api_web_contents.cc
const SkBitmap& bitmap,
                       content::ReadbackResponse response) {
  
  
  const_cast<SkBitmap&>(bitmap).setAlphaType(kPremul_SkAlphaType);
  callback.Run(gfx::Image::CreateFrom1xBitmap(bitmap));
}
}  
struct WebContents::FrameDispatchHelper {
  WebContents* api_web_contents;
  content::RenderFrameHost* rfh;
  bool Send(IPC::Message* msg) { return rfh->Send(msg); }
  void OnSetTemporaryZoomLevel(double level, IPC::Message* reply_msg) {
    api_web_contents->OnSetTemporaryZoomLevel(rfh, level, reply_msg);
  }
  void OnGetZoomLevel(IPC::Message* reply_msg) {
    api_web_contents->OnGetZoomLevel(rfh, reply_msg);
  }
  void OnRendererMessageSync(const base::string16& channel,
                             const base::ListValue& args,
                             IPC::Message* message) {
    api_web_contents->OnRendererMessageSync(rfh, channel, args, message);
  }
};
WebContents::WebContents(v8::Isolate* isolate,