Replaced Ok() occurrences with IsOk() throughout trunk.

Additionally renamed wxOSX' private wxNativePrinterDC::Ok() function to IsOk().

Didn't deprecate the various Ok() functions: given the amount of changes already introduced in 3.0 a trivial one like this seems more suitable for after 3.0.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67681 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/artprov/artbrows.cpp

@@ -34,7 +34,7 @@
     { \
         int ind; \
         wxIcon icon = wxArtProvider::GetIcon(id, client, size); \
-        if ( icon.Ok() ) \
+        if ( icon.IsOk() ) \
             ind = images->Add(icon); \
         else \
             ind = 0; \