Check if malformed fixture exists first

Now if somebody by mistake will remove malformed files test will raise error.

actionview/test/template/render_test.rb

@@ -376,6 +376,7 @@ def test_render_knows_about_types_registered_when_extensions_are_checked_earlier
   def test_render_ignores_templates_with_malformed_template_handlers
     ActiveSupport::Deprecation.silence do
       %w(malformed malformed.erb malformed.html.erb malformed.en.html.erb).each do |name|
+        assert File.exists?(File.expand_path("#{FIXTURE_LOAD_PATH}/test/malformed/#{name}~")), "Malformed file (#{name}~) which should be ignored does not exists"
         assert_raises(ActionView::MissingTemplate) { @view.render(:file => "test/malformed/#{name}") }
       end
     end