Merge wxQT branch into the trunk.

This merges in the latest sources from GSoC 2014 wxQt project with just a few
minor corrections, mostly undoing wrong changes to common files in that branch
(results of a previous bad merge?) and getting rid of whitespace-only changes.
Also remove debug logging from wxGrid.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77455 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msgdlg.h

@@ -185,7 +185,6 @@ public:
         DoSetCustomLabel(m_help, help);
         return true;
     }
-
     // test if any custom labels were set
     bool HasCustomLabels() const
     {
@@ -300,6 +299,8 @@ private:
     #include "wx/gtk/msgdlg.h"
 #elif defined(__WXMAC__)
     #include "wx/osx/msgdlg.h"
+#elif defined(__WXQT__)
+    #include "wx/qt/msgdlg.h"
 #endif
 
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