Only select the first radio button if there is one in wxMSW wxRadioBox.

Don't call SetSelection(0) if the radio box is empty.

See #16630.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@78045 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Don't leave wxSubwindows::m_ids uninitialized.

Normally it's initialized by calling Create(), but don't crash deleting an
invalid pointer in the dtor if Create() hadn't been called.

See #16630.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@78046 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775