Make wxPreferencesEditor dtor virtual.

Mainly just to suppress g++ warnings about a class with virtual functions but
non-virtual dtor, this class isn't really supposed to be used polymorphically.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74016 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Try using wxString::ToCDouble() instead of ToDouble() in wxAny case.

Apparently enabling the call to ToDouble() in the test is enough to corrupt
the heap in wxOSX PPC build. No idea how can this be possible but try to check
if using ToCDouble() helps...

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74017 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775