add missing `:nodoc:` for recent refactorings. [ci skip]

Adding `# :nodoc:` to the parent `class` / `module` is not going
to ignore nested classes or modules.

There is a modifier `# :nodoc: all` but sadly the containing class
or module will continue to be in the docs.

/cc @sgrif

1 files changed, 2 insertions, 2 deletions

diff --git a/activerecord/lib/active_record/attribute_decorators.rb b/activerecord/lib/active_record/attribute_decorators.rb
index 92627f8d5d..5745bbe0e3 100644
--- a/activerecord/lib/active_record/attribute_decorators.rb
+++ b/activerecord/lib/active_record/attribute_decorators.rb
@@ -7,7 +7,7 @@ module ActiveRecord
       self.attribute_type_decorations = TypeDecorator.new
     end
 
-    module ClassMethods
+    module ClassMethods # :nodoc:
       def decorate_attribute_type(column_name, decorator_name, &block)
         matcher = ->(name, _) { name == column_name.to_s }
         key = "_#{column_name}_#{decorator_name}"
@@ -32,7 +32,7 @@ module ActiveRecord
       end
     end
 
-    class TypeDecorator
+    class TypeDecorator # :nodoc:
       delegate :clear, to: :@decorations
 
       def initialize(decorations = {})