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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
return;
  }
  printing::CompletionCallback callback;
  if (args->Length() == 2 && !args->GetNext(&callback)) {
    args->ThrowError(
        "ws.print(): Invalid optional callback provided.");
    return;
  }
   Set optional silent printing
  bool silent = false;
  options.Get("silent", &silent);
  bool print_background = false;
  options.Get("printBackground", &print_background);
  settings.SetBoolKey(printing::kSettingShouldPrintBackgrounds,
                      print_background);
   Set custom margin settings
  gin_helper::Dictionary margins =
      gin::Dictionary::CreateEmpty(args->isolate());
  if (options.Get("margins", &margins)) {
    printing::MarginType margin_type = printing::DEFAULT_MARGINS;
    margins.Get("marginType", &margin_type);
    settings.SetIntKey(printing::kSettingMarginsType, margin_type);
    if (margin_type == printing::CUSTOM_MARGINS) {
      base::Value custom_margins(base::Value::Type::DICTIONARY);
      int top = 0;
      margins.Get("top", &top);
      custom_margins.SetIntKey(printing::kSettingMarginTop, top);
      int bottom = 0;
      margins.Get("bottom", &bottom);
      custom_margins.SetIntKey(printing::kSettingMarginBottom, bottom);