- Electron version: 1.3.3
- Operating system: Windows

I have noticed that a `webview` will emit the `did-navigate-in-page` event when an IFRAME included in the page finishes loading.

Is this the desired behavior? The documentation implies that this event shall only trigger when the main frame's URL hash changes. In any case, a flag `isMainFrame` would be helpful here.

atom/browser/api/atom_api_web_contents.cc
net::HttpResponseHeaders* headers) {
    base::DictionaryValue response_headers;
    if (headers) {
      size_t iter = 0;
      std::string key;
      std::string value;
      while (headers->EnumerateHeaderLines(&iter, &key, &value)) {
        key = base::ToLowerASCII(key);
        if (response_headers.HasKey(key)) {
          base::ListValue* values = nullptr;
          if (response_headers.GetList(key, &values))
            values->AppendString(value);
        } else {
          std::unique_ptr<base::ListValue> values(new base::ListValue());
          values->AppendString(value);
          response_headers.Set(key, std::move(values));
        }
      }
    }
    return ConvertToV8(isolate, response_headers);
  }
};
template<>
struct Converter<content::SavePageType> {
  static bool FromV8(v8::Isolate* isolate, v8::Local<v8::Value> val,