- 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
const std::string& frame_name,
                                 WindowOpenDisposition disposition) {
  if (type_ == BROWSER_WINDOW || type_ == OFF_SCREEN)
    Emit("-new-window", target_url, frame_name, disposition);
  else
    Emit("new-window", target_url, frame_name, disposition);
}
content::WebContents* WebContents::OpenURLFromTab(
    content::WebContents* source,
    const content::OpenURLParams& params) {
  if (params.disposition != CURRENT_TAB) {
    if (type_ == BROWSER_WINDOW || type_ == OFF_SCREEN)
      Emit("-new-window", params.url, "", params.disposition);
    else
      Emit("new-window", params.url, "", params.disposition);
    return nullptr;
  }
  
  if (Emit("will-navigate", params.url))
    return nullptr;
  return CommonWebContentsDelegate::OpenURLFromTab(source, params);
}
void WebContents::BeforeUnloadFired(content::WebContents* tab,