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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
if (mate::ConvertFromV8(isolate, input_event, &keyboard_event)) {
      view->ProcessKeyboardEvent(keyboard_event, ui::LatencyInfo());
      return;
    }
  } else if (type == blink::WebInputEvent::kMouseWheel) {
    blink::WebMouseWheelEvent mouse_wheel_event;
    if (mate::ConvertFromV8(isolate, input_event, &mouse_wheel_event)) {
      view->ProcessMouseWheelEvent(mouse_wheel_event, ui::LatencyInfo());
      return;
    }
  }
  isolate->ThrowException(
      v8::Exception::Error(mate::StringToV8(isolate, "Invalid event object")));
}
void WebContents::BeginFrameSubscription(mate::Arguments* args) {
  bool only_dirty = false;
  FrameSubscriber::FrameCaptureCallback callback;
  args->GetNext(&only_dirty);
  if (!args->GetNext(&callback)) {
    args->ThrowError();
    return;
  }
  auto* const view = web_contents()->GetRenderWidgetHostView();
  if (view) {
    std::unique_ptr<FrameSubscriber> frame_subscriber(
        new FrameSubscriber(isolate(), view, callback, only_dirty));
    view->BeginFrameSubscription(std::move(frame_subscriber));
  }
}
void WebContents::EndFrameSubscription() {