remove default wxDC ctor to make it impossible to construct DCs without the associated wxDCImpl (this breaks compilation of classes such as wxMirrorDC instead of crashing at run-time); fixed wxMirrorDC compilation after breaking it; renamed wxDCFactory::GetFactory() to just Get(), no need to be repetitive

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@50385 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/dcprint.h

@@ -27,11 +27,13 @@ class WXDLLIMPEXP_CORE wxPrinterDC : public wxDC
 public:
     wxPrinterDC();
     wxPrinterDC(const wxPrintData& data);
-    virtual ~wxPrinterDC();
 
     wxRect GetPaperRect();
     int GetResolution();
 
+protected:
+    wxPrinterDC(wxDCImpl *impl) : wxDC(impl) { }
+
 private:
     DECLARE_DYNAMIC_CLASS(wxPrinterDC)
 };