Revert "Improve custom configuration"

This reverts commit de4891344ccc074f6d5693f4fac6ad610584e336.

Conflicts:
	railties/lib/rails/railtie/configuration.rb

It added regression. Will be back after the beta

2 files changed, 15 insertions, 19 deletions

diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md
index b90e5025e2..f710b8bac9 100644
--- a/guides/source/4_2_release_notes.md
+++ b/guides/source/4_2_release_notes.md
@@ -78,24 +78,22 @@ Please refer to the [Changelog][railties] for detailed changes.
 *   Introduced an `after_bundle` callback for use in Rails templates.
     ([Pull Request](https://github.com/rails/rails/pull/16359))
 
-*   Custom configuration options can be chained:
+*   Introduced the `x` namespace for defining custom configuration options:
 
     ```ruby
     # config/environments/production.rb
-    config.payment_processing.schedule = :daily
-    config.payment_processing.retries  = 3
-    config.resque = { timeout: 60, inline_jobs: :always }
-    config.super_debugger = true
+    config.x.payment_processing.schedule = :daily
+    config.x.payment_processing.retries  = 3
+    config.x.super_debugger = true
     ```
 
     These options are then available through the configuration object:
 
     ```ruby
-    Rails.configuration.payment_processing.schedule # => :daily
-    Rails.configuration.payment_processing.retries  # => 3
-    Rails.configuration.resque.timeout              # => 60
-    Rails.configuration.resque.inline_jobs          # => :always
-    Rails.configuration.super_debugger              # => true
+    Rails.configuration.x.payment_processing.schedule # => :daily
+    Rails.configuration.x.payment_processing.retries  # => 3
+    Rails.configuration.x.super_debugger              # => true
+    Rails.configuration.x.super_debugger.not_set      # => nil
     ```
 
     ([Commit](https://github.com/rails/rails/commit/611849772dd66c2e4d005dcfe153f7ce79a8a7db))
diff --git a/guides/source/configuring.md b/guides/source/configuring.md
index 6922dd681a..801cef5ca6 100644
--- a/guides/source/configuring.md
+++ b/guides/source/configuring.md
@@ -1006,18 +1006,16 @@ Custom configuration
 You can configure your own code through the Rails configuration object with custom configuration. It works like this:
 
   ```ruby
-  config.payment_processing.schedule = :daily
-  config.payment_processing.retries  = 3
-  config.resque = { timeout: 60, inline_jobs: :always }
-  config.super_debugger = true
+  config.x.payment_processing.schedule = :daily
+  config.x.payment_processing.retries  = 3
+  config.x.super_debugger = true
   ```
 
 These configuration points are then available through the configuration object:
 
   ```ruby
-  Rails.configuration.payment_processing.schedule # => :daily
-  Rails.configuration.payment_processing.retries  # => 3
-  Rails.configuration.resque.timeout              # => 60
-  Rails.configuration.resque.inline_jobs          # => :always
-  Rails.configuration.super_debugger              # => true
+  Rails.configuration.x.payment_processing.schedule # => :daily
+  Rails.configuration.x.payment_processing.retries  # => 3
+  Rails.configuration.x.super_debugger              # => true
+  Rails.configuration.x.super_debugger.not_set      # => nil
   ```