build fix for wxUSE_THREADS==0

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@76309 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
build fix for wxUSE_DRAG_AND_DROP==0

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@76310 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
build fix for wxUSE_TOGGLEBTN==0

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@76311 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775