- 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
content::RenderFrameHost* frame,
    const content::BluetoothChooser::EventHandler& event_handler) {
  std::unique_ptr<BluetoothChooser> bluetooth_chooser(
      new BluetoothChooser(this, event_handler));
  return std::move(bluetooth_chooser);
}
void WebContents::BeforeUnloadFired(const base::TimeTicks& proceed_time) {
  
  
}
void WebContents::RenderViewDeleted(content::RenderViewHost* render_view_host) {
  Emit("render-view-deleted", render_view_host->GetProcess()->GetID());
}
void WebContents::RenderProcessGone(base::TerminationStatus status) {
  Emit("crashed");
}
void WebContents::PluginCrashed(const base::FilePath& plugin_path,
                                base::ProcessId plugin_pid) {
  content::WebPluginInfo info;
  auto plugin_service = content::PluginService::GetInstance();
  plugin_service->GetPluginInfoByPath(plugin_path, &info);
  Emit("plugin-crashed", info.name, info.version);
}
void WebContents::MediaStartedPlaying(const MediaPlayerId& id) {
  Emit("media-started-playing");
}
void WebContents::MediaStoppedPlaying(const MediaPlayerId& id) {