1. undid my wrong fix to wxWindowBase::Centre

2. corrected fatal bug in wxCheckLstBox (double deletion of items)
3. wxTextCtrl::SetValue() only does it if the new text is different from
   the old one
4. wxBitmap(const wxIcon&) ctor added
5. compilation fixes for VC++ and generic Win32 implementation of
   wxGetCurrentTime() in timercmn.cpp


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@4534 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/wincmn.cpp

@@ -354,9 +354,8 @@ void wxWindowBase::Centre(int direction)
         yNew += posParent.y;
     }
 
-    // move the centre of this window to this position (not the upper left
-    // corner as it was done before)
-    Move(xNew - width / 2, yNew - height / 2);
+    // move the centre of this window to this position
+    Move(xNew, yNew);
 }
 
 // fits the window around the children