Attempt to correct mysterious MSVC6 compilation error.

For some reasons MSVC6 refuses to compile TestData struct initialization. Try
to work around it by not using wxULongLong as this looks like the only thing
which might be confusing it.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@63874 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/filename/filenametest.cpp

@@ -485,7 +485,7 @@ void FileNameTestCase::TestGetHumanReadable()
     static const struct TestData
     {
         const char *result;
-        wxULongLong size;
+        int size;
         int prec;
         wxSizeConvention conv;
     } testData[] =