Merge pull request #26306 from kamipo/remove_under_ruby-1.9

Remove "Under Ruby 1.9" [ci skip]

activerecord/lib/active_record/core.rb

@@ -541,15 +541,15 @@ def slice(*methods)
 
     private
 
-    # Under Ruby 1.9, Array#flatten will call #to_ary (recursively) on each of the elements
-    # of the array, and then rescues from the possible NoMethodError. If those elements are
-    # ActiveRecord::Base's, then this triggers the various method_missing's that we have,
-    # which significantly impacts upon performance.
-    #
-    # So we can avoid the method_missing hit by explicitly defining #to_ary as nil here.
-    #
-    # See also http://tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary.html
-      def to_ary # :nodoc:
+      # +Array#flatten+ will call +#to_ary+ (recursively) on each of the elements of
+      # the array, and then rescues from the possible +NoMethodError+. If those elements are
+      # +ActiveRecord::Base+'s, then this triggers the various +method_missing+'s that we have,
+      # which significantly impacts upon performance.
+      #
+      # So we can avoid the +method_missing+ hit by explicitly defining +#to_ary+ as +nil+ here.
+      #
+      # See also http://tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary.html
+      def to_ary
         nil
       end