The font is explicitly documented as being possibly NULL in the base class and
wxMSW handles NULL font just fine, so also handle it in the GTK version.
See #14706.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72844 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Add a new private wxTextMeasure class implementing methods for measuring text
and move the often duplicated (but not always identically) code for doing the
same from wxDC and wxWindow into it.
Currently this class is only really implemented in wxMSW and wxGTK.
Also extend the test for text measuring functions and rename it to
MeasuringTextTestCase from MeasuringContextTestCase as it's not wxGC-specific
any more.
Closes#14705.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72699 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
