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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
#if defined(OS_MACOSX)
  base::ScopedCFTypeRef<CFStringRef> new_printer_id(
      base::SysUTF16ToCFStringRef(device_name));
  PMPrinter new_printer = PMPrinterCreateFromPrinterID(new_printer_id.get());
  bool printer_exists = new_printer != nullptr;
  PMRelease(new_printer);
  return printer_exists;
#elif defined(OS_WIN)
  printing::ScopedPrinterHandle printer;
  return printer.OpenPrinterWithName(device_name.c_str());
#endif
  return true;
}
base::string16 GetDefaultPrinterAsync() {