Add tests in all the time that was omitted for Ruby 1.8.x

test/test_convertible.rb

@@ -36,7 +36,6 @@ class TestConvertible < Test::Unit::TestCase
       assert_no_match /undefined class\/module DoesNotExist/, out
     end
 
-    if RUBY_VERSION >= '1.9.2'
     should "not parse if there is encoding error in file" do
       name = 'broken_front_matter3.erb'
       out = capture_stdout do
@@ -48,4 +47,3 @@ class TestConvertible < Test::Unit::TestCase
     end
   end
 end
-end