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Ref #19447

### Issue Details

* **Electron Version:**
  * 9.0.0-beta.24
* **Operating System:**
  * macOS 10.15, Windows 10
* **Last Known Working Electron version:**
  * none

### Expected Behavior
`e.sender` object received from an extension background page should have `webPreferences` and `session` initialized. It looks like `options` in `api::WebContents` constructor don't get initialized properly for an extension background page.

### Actual Behavior
`e.sender` object doesn't have `session` and `e.sender.getWebPreferences()` returns `null`.

### To Reproduce
https://github.com/sentialx/electron-quick-start/tree/extensions/no-session

Just run it and you will see something like this:
![image](https://user-images.githubusercontent.com/11065386/82097607-82994400-9703-11ea-8291-0eb987d8aca0.png)

### Additional Information
This is a real blocker for anyone who would want to provide own `chrome` APIs in background pages initialized from different sessions.
shell/browser/api/electron_api_web_contents.cc
frame_to_bindings_map_.erase(it);
}
void Ws::DidStartNavigation(
    content::NavigationHandle* navigation_handle) {
  EmitNavigationEvent("did-start-navigation", navigation_handle);
}
void Ws::DidRedirectNavigation(
    content::NavigationHandle* navigation_handle) {
  EmitNavigationEvent("did-redirect-navigation", navigation_handle);
}
void Ws::DidFinishNavigation(
    content::NavigationHandle* navigation_handle) {
  if (!navigation_handle->HasCommitted())
    return;
  bool is_main_frame = navigation_handle->IsInMainFrame();
  content::RenderFrameHost* frame_host =
      navigation_handle->GetRenderFrameHost();
  int frame_process_id = -1, frame_routing_id = -1;
  if (frame_host) {
    frame_process_id = frame_host->GetProcess()->GetID();
    frame_routing_id = frame_host->GetRoutingID();
  }
  if (!navigation_handle->IsErrorPage()) {
     FIXME: All the Emit() calls below could potentially result in |this|
     being destroyed (by JS listening for the event and calling
     ws.destroy()).
    auto url = navigation_handle->GetURL();
    bool is_same_document = navigation_handle->IsSameDocument();
    if (is_same_document) {
      Emit("did-navigate-in-page", url, is_main_frame, frame_process_id,