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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_routing_id);
    } else {
      const net::HttpResponseHeaders* http_response =
          navigation_handle->GetResponseHeaders();
      std::string http_status_text;
      int http_response_code = -1;
      if (http_response) {
        http_status_text = http_response->GetStatusText();
        http_response_code = http_response->response_code();
      }
      Emit("did-frame-navigate", url, http_response_code, http_status_text,
           is_main_frame, frame_process_id, frame_routing_id);
      if (is_main_frame) {
        Emit("did-navigate", url, http_response_code, http_status_text);
      }
    }
    if (IsGuest())
      Emit("load-commit", url, is_main_frame);
  } else {
    auto url = navigation_handle->GetURL();
    int code = navigation_handle->GetNetErrorCode();
    auto description = net::ErrorToShortString(code);
    Emit("did-fail-provisional-load", code, description, url, is_main_frame,
         frame_process_id, frame_routing_id);
     Do not emit "did-fail-load" for canceled requests.
    if (code != net::ERR_ABORTED)
      Emit("did-fail-load", code, description, url, is_main_frame,
           frame_process_id, frame_routing_id);
  }
}