Remove deprecation warning from attribute_missing

for attributes that are columns.

activerecord/CHANGELOG.md

+*   Remove deprecation warning from `attribute_missing` for attributes that are columns.
+
+    *Arun Agrawal*
+
 *   Remove extra decrement of transaction deep level.
 
     Fixes: #4566

activerecord/lib/active_record/attribute_methods.rb

@@ -176,20 +176,6 @@ def method_missing(method, *args, &block) # :nodoc:
       end
     end
 
-    def attribute_missing(match, *args, &block) # :nodoc:
-      if self.class.columns_hash[match.attr_name]
-        ActiveSupport::Deprecation.warn(
-          "The method `#{match.method_name}', matching the attribute `#{match.attr_name}' has " \
-          "dispatched through method_missing. This shouldn't happen, because `#{match.attr_name}' " \
-          "is a column of the table. If this error has happened through normal usage of Active " \
-          "Record (rather than through your own code or external libraries), please report it as " \
-          "a bug."
-        )
-      end
-
-      super
-    end
-
     # A Person object with a name attribute can ask <tt>person.respond_to?(:name)</tt>,
     # <tt>person.respond_to?(:name=)</tt>, and <tt>person.respond_to?(:name?)</tt>
     # which will all return +true+. It also define the attribute methods if they have

activerecord/test/cases/attribute_methods_test.rb

@@ -759,21 +759,6 @@ def test_instance_method_should_be_defined_on_the_base_class
     assert subklass.method_defined?(:id), "subklass is missing id method"
   end
 
-  def test_dispatching_column_attributes_through_method_missing_deprecated
-    Topic.define_attribute_methods
-
-    topic = Topic.new(:id => 5)
-    topic.id = 5
-
-    topic.method(:id).owner.send(:undef_method, :id)
-
-    assert_deprecated do
-      assert_equal 5, topic.id
-    end
-  ensure
-    Topic.undefine_attribute_methods
-  end
-
   def test_read_attribute_with_nil_should_not_asplode
     assert_equal nil, Topic.new.read_attribute(nil)
   end