Change `ActionDispatch::Response#content_type` returning Content-Type header as it is

Since #35709, `Response#conten_type` returns only MIME type correctly.
It is a documented behavior that this method only returns MIME type, so
this change seems appropriate.
https://github.com/rails/rails/blob/39de7fac0507070e3c5f8b33fbad6fced84d97ed/actionpack/lib/action_dispatch/http/response.rb#L245-L249

But unfortunately, some users expect this method to return all
Content-Type that does not contain charset. This seems to be breaking
changes.

We can change this behavior with the deprecate cycle.
But, in that case, a method needs that include Content-Type with
additional parameters. And that method name is probably the
`content_type` seems to properly.

So I changed the new behavior to more appropriate `media_type` method.
And `Response#content_type` changed (as the method name) to return Content-Type
header as it is.

Fixes #35709.

[Rafael Mendonça França & Yuuji Yaginuma ]

1 files changed, 2 insertions, 2 deletions

diff --git a/actionpack/test/controller/render_xml_test.rb b/actionpack/test/controller/render_xml_test.rb
index a72d14e4bb..7d61076e7c 100644
--- a/actionpack/test/controller/render_xml_test.rb
+++ b/actionpack/test/controller/render_xml_test.rb
@@ -92,11 +92,11 @@ class RenderXmlTest < ActionController::TestCase
 
   def test_should_render_xml_but_keep_custom_content_type
     get :render_xml_with_custom_content_type
-    assert_equal "application/atomsvc+xml", @response.content_type
+    assert_equal "application/atomsvc+xml", @response.media_type
   end
 
   def test_should_use_implicit_content_type
     get :implicit_content_type, format: "atom"
-    assert_equal Mime[:atom], @response.content_type
+    assert_equal Mime[:atom], @response.media_type
   end
 end