- Electron version: 1.2.2
- Operating system: Linux

This is a problem only in linux. It works in OSX.

``` javascript
win.hide()
win.capturePage(function(img){
 // never called
})
```

shell/browser/api/electron_api_web_contents.cc
content::ChildProcessSecurityPolicy::GetInstance()->GrantCommitOrigin(
      ontents()->GetMainFrame()->GetProcess()->GetID(),
      url::Origin::Create(url));
}
void WebContents::NotifyUserActivation() {
  content::RenderFrameHost* frame = ontents()->GetMainFrame();
  if (frame)
    frame->NotifyUserActivation(
        blink::mojom::UserActivationNotificationType::kInteraction);
}
v8::Local<v8::Promise> WebContents::TakeHeapSnapshot(
    v8::Isolate* isolate,
    const base::FilePath& file_path) {
  gin_helper::Promise<void> promise(isolate);
  v8::Local<v8::Promise> handle = promise.GetHandle();
  base::ThreadRestrictions::ScopedAllowIO allow_io;
  base::File file(file_path,
                  base::File::FLAG_CREATE_ALWAYS | base::File::FLAG_WRITE);
  if (!file.IsValid()) {
    promise.RejectWithErrorMessage("takeHeapSnapshot failed");
    return handle;
  }
  auto* frame_host = ontents()->GetMainFrame();
  if (!frame_host) {
    promise.RejectWithErrorMessage("takeHeapSnapshot failed");
    return handle;
  }
  if (!frame_host->IsRenderFrameCreated()) {