It's going to be removed from Chromium, see https://crbug.com/812523.

/cc @electron/code-owners 
chromium_src/chrome/browser/certificate_manager_model.h
class ResourceContext;
}  
class CertificateManagerModel {
 public:
  typedef base::Callback<void(std::unique_ptr<CertificateManagerModel>)>
      CreationCallback;
  
  
  
  static void Create(content::BrowserContext* browser_context,
                     const CreationCallback& callback);
  ~CertificateManagerModel();
  bool is_user_db_available() const { return is_user_db_available_; }
  
  const net::NSSCertDatabase* cert_db() const { return cert_db_; }
  
  
  
  
  int ImportFromPKCS12(PK11SlotInfo* slot_info,
                       const std::string& data,