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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
print_backend->EnumeratePrinters(&printers);
  }
  return printers;
}
v8::Local<v8::Promise> Ws::PrintToPDF(base::DictionaryValue settings) {
  gin_helper::Promise<v8::Local<v8::Value>> promise(isolate());
  v8::Local<v8::Promise> handle = promise.GetHandle();
  PrintPreviewMessageHandler::FromWs(ontents())
      ->PrintToPDF(std::move(settings), std::move(promise));
  return handle;
}
#endif
void Ws::AddWorkSpace(gin_helper::Arguments* args,
                               const base::FilePath& path) {
  if (path.empty()) {
    args->ThrowError("path cannot be empty");
    return;
  }
  DevToolsAddFileSystem(std::string(), path);
}
void Ws::RemoveWorkSpace(gin_helper::Arguments* args,
                                  const base::FilePath& path) {
  if (path.empty()) {
    args->ThrowError("path cannot be empty");
    return;
  }
  DevToolsRemoveFileSystem(path);
}
void Ws::Undo() {
  ontents()->Undo();