define returns different result when checking _.contents

[David Hunter]

I have confirmed a change in operation between 4.5->5.0.403 and 5.0.449
where a defined container in 5.0.449 now returns true and and empty string when
checking _.contents when no contents are supplied.

e.g

<define container="tag">
  <if variable="_.contents">"&_.contents;"</if>
</define>

<tag/> -> 5.0.403 returns nothing . 5.0.449 returns "".
<tag></tag> -> 5.0.403 returns nothing. 5.0.449 returns "".
<tag> </tag> -> 5.0.403 returns " ".  5.0.449 returns " ".

can someone confirm if this is an expected change or a bug that required fixing.

David Hunter.