tdf#103690: Set up notifications only after VCL has been initialised

On some Macs, it seems that LibreOffice (or any app?) gets an
NSApplicationDidChangeScreenParametersNotification as soon as it has
started and asked for such a notification. Our handler for that
notification assumes that VCL is initialised. Thus we should not ask
for such notifications before VCL has been initialised.

I could not reproduce the reported crash with an unmodified
LibreOffice, only after inserting a sleep after the notifications had
been set up. But I am fairly sure this change fixes the problem.

Change-Id: I18d342eb7dc0c77cb7fc8623756bead65a1bd329
Reviewed-on: https://gerrit.libreoffice.org/50164Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tor Lillqvist <tml@collabora.com>

vcl/inc/salinst.hxx

@@ -205,6 +205,10 @@ void DeInitSalData();                       // called from Application-Dtor
 
 void InitSalMain();
 
+#ifdef MACOSX
+void postInitVCLinitNSApp();
+#endif
+
 #endif // INCLUDED_VCL_INC_SALINST_HXX
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

vcl/osx/salinst.cxx

@@ -157,7 +157,10 @@ static void initNSApp()
 
     // activate our delegate methods
     [NSApp setDelegate: NSApp];
+}
 
+void postInitVCLinitNSApp()
+{
     [[NSNotificationCenter defaultCenter] addObserver: NSApp
                                           selector: @selector(systemColorsChanged:)
                                           name: NSSystemColorsDidChangeNotification

vcl/source/app/svmain.cxx

@@ -187,6 +187,10 @@ int ImplSVMain()
 
     bool bInit = isInitVCL() || InitVCL();
 
+#ifdef MACOSX
+    postInitVCLinitNSApp();
+#endif
+
     if( bInit )
     {
         // call application main