Remove DLL export declaration from wxScrolled.

As this class has only inline methods it doesn't need to be exported from the
DLL and actually exporting it results in linking problems when using
wxScrolled<wxWindow> (which, unlike wxScrolled<wxPanel>, is not used in wx
itself and so doesn't seem to be instantiated) in DLL client even with VC > 6.

An alternative solution would be to change WXDLLIMPEXP_TEMPLATE_INSTANCE_CORE
macro to explicitly instantiate the template in the DLL even for VC > 6 but
this wouldn't solve the problem for wxScrolled<CustomClass> while removing the
DLL export declaration should.

Also use wxScrolled<wxWindow> in addition to wxScrolled<wxPanel> in the scroll
sample to test that it links correctly.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62036 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/scrolwin.h

@@ -333,9 +333,9 @@ struct WXDLLIMPEXP_CORE wxScrolledT_Helper
 // but wxScrolledWindow includes wxControlContainer functionality and that's
 // not always desirable.
 template<class T>
-class WXDLLIMPEXP_CORE wxScrolled : public T,
-                                    public wxScrollHelper,
-                                    private wxScrolledT_Helper
+class wxScrolled : public T,
+                   public wxScrollHelper,
+                   private wxScrolledT_Helper
 {
 public:
     wxScrolled() : wxScrollHelper(this) { }
@@ -409,12 +409,6 @@ private:
 #endif
 };
 
-// VC++ <= 6 requires this; it's unlikely any other specializations would
-// be needed by user code _and_ they were using VC6, so we list only wxWindow
-// (typical use) and wxPanel (wxScrolledWindow use) specializations here
-WXDLLIMPEXP_TEMPLATE_INSTANCE_CORE( wxScrolled<wxPanel> )
-WXDLLIMPEXP_TEMPLATE_INSTANCE_CORE( wxScrolled<wxWindow> )
-
 // for compatibility with existing code, we provide wxScrolledWindow
 // "typedef" for wxScrolled<wxPanel>. It's not a real typedef because we
 // want wxScrolledWindow to show in wxRTTI information (the class is widely