There is no need to clear the control contents before loading a file into it
because LoadFile() is supposed to do this on its own (although currently it
doesn't, which will be fixed soon).
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72593 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775