Google authentication added

app/controllers/users/omniauth_callbacks_controller.rb

@@ -11,6 +11,10 @@ class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
     login_via 'StackExchange'
   end
 
+  def google_oauth2
+    login_via 'Google'
+  end
+
   def login_via(provider_name)
     # You need to implement the method below in your model (e.g. app/models/user.rb)
     @user = User.from_omniauth(request.env["omniauth.auth"])