Revert "DEV: Let OmniAuth strategies return auth result. (#7833)"

This reverts commit dc5eb76551.

It is better to keep any custom redirect logic within omniauth, without relying on the app

app/controllers/users/omniauth_callbacks_controller.rb

@@ -19,15 +19,6 @@ class Users::OmniauthCallbacksController < ApplicationController
   skip_before_action :verify_authenticity_token, only: :complete
 
   def complete
-    if result = request.env["omniauth.result"]
-      @auth_result = result
-
-      return respond_to do |format|
-        format.html
-        format.json { render json: @auth_result.to_client_hash }
-      end
-    end
-
     auth = request.env["omniauth.auth"]
     raise Discourse::NotFound unless request.env["omniauth.auth"]
 

spec/requests/omniauth_callbacks_controller_spec.rb

@@ -12,7 +12,6 @@ RSpec.describe Users::OmniauthCallbacksController do
 
   after do
     Rails.application.env_config["omniauth.auth"] = OmniAuth.config.mock_auth[:google_oauth2] = nil
-    Rails.application.env_config["omniauth.result"] = nil
     OmniAuth.config.test_mode = false
   end
 
@@ -80,25 +79,6 @@ RSpec.describe Users::OmniauthCallbacksController do
     end
   end
 
-  describe '.complete' do
-    it 'will return result if present' do
-      result = Auth::Result.new
-      result.user = Fabricate(:user)
-      result.authenticated = true
-      result.destination_url = "/anotherpath"
-
-      Rails.application.env_config["omniauth.origin"] = '/somepath'
-      Rails.application.env_config["omniauth.result"] = result
-
-      get "/auth/test/callback.json"
-      response_body = JSON.parse(response.body)
-
-      expect(response.status).to eq(200)
-      expect(response_body["authenticated"]).to eq(true)
-      expect(response_body["destination_url"]).to eq("/anotherpath")
-    end
-  end
-
   context 'Google Oauth2' do
     before do
       SiteSetting.enable_google_oauth2_logins = true