CueSettingVertical.BadKeyword assertion makes no sense

```C++
TEST_F(CueSettingVertical, BadKeyword)
{
  loadVtt( "cue-settings/vertical/bad-keyword.vtt", 1 );
  const Error &err = getError( 0 );

  ASSERT_EQ( 50, getCue( 0 ).isHorizontal() );

  ASSERT_EQ( WEBVTT_INVALID_CUESETTING, err.error() );
  ASSERT_EQ( 3, err.line() );
  ASSERT_EQ( 25, err.column() );
}
```
isHorizontal() returns bool, so `50` is never going to happen.