- Electron version: 1.4.0
- Operating system: OS X 10.10.5

I've been using the following code to send Tab key events to a webview in my project:

``` js
const webContents = webView.getWebContents();
const keyEvent = {
  type: 'keyDown',
  keyCode: 'Tab'
};

webContents.sendInputEvent(keyEvent);
```

I have had no issues with this until the recent update to 1.4.0.

The last version the above code works in OS X is **1.3.7**. I've tried this with the latest versions of Electron (1.4.1 & 1.4.2) with the same results.

Am I doing something wrong here? Is this a known issue?

atom/common/native_mate_converters/blink_converter.cc
v8::Isolate* isolate,
    v8::Local<v8::Value> val,
    blink::WebFindOptions* out) {
  mate::Dictionary dict;
  if (!ConvertFromV8(isolate, val, &dict))
    return false;
  dict.Get("forward", &out->forward);
  dict.Get("matchCase", &out->matchCase);
  dict.Get("findNext", &out->findNext);
  dict.Get("wordStart", &out->wordStart);
  dict.Get("medialCapitalAsWordStart", &out->medialCapitalAsWordStart);
  return true;
}
v8::Local<v8::Value> Converter<blink::WebContextMenuData::MediaType>::ToV8(