Make generic wxDataViewProgressRenderer fill the entire cell.

Make generic wxDataViewProgressRenderer fill the entire cell.

After the fixes in the previous commit it is finally possibly to make the
progress renderer expand to the entire cell area instead of taking a
fixed width, it is enough to simply override RenderWithAttr() instead of
Render() and ignore the alignment as this avoids the use of (arbitrary and
hardcoded) wxDataViewProgressRenderer::GetSize().

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62394 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775