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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
const std::string& channel,
                                 v8::Local<v8::Value> args) {
  blink::CloneableMessage message;
  if (!gin::ConvertFromV8(isolate(), args, &message)) {
    isolate()->ThrowException(v8::Exception::Error(
        gin::StringToV8(isolate(), "Failed to serialize arguments")));
    return false;
  }
  return SendIPCMessageWithSender(internal, send_to_all, channel,
                                  std::move(message));
}
bool Ws::SendIPCMessageWithSender(bool internal,
                                           bool send_to_all,
                                           const std::string& channel,
                                           blink::CloneableMessage args,
                                           int32_t sender_id) {
  std::vector<content::RenderFrameHost*> target_hosts;
  if (!send_to_all) {
    auto* frame_host = ontents()->GetMainFrame();
    if (frame_host) {
      target_hosts.push_back(frame_host);
    }
  } else {
    target_hosts = ontents()->GetAllFrames();
  }
  for (auto* frame_host : target_hosts) {
    mojo::AssociatedRemote<mojom::ElectronRenderer> electron_renderer;
    frame_host->GetRemoteAssociatedInterfaces()->GetInterface(
        &electron_renderer);
    electron_renderer->Message(internal, false, channel, args.ShallowClone(),