fixed processing of the implicit wxTextCtrl accelerators (Ctrl-C/V/X)

without breaking all the others by using a new MSWShouldPreProcessMessage()
function


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@11282 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/textctrl.h

@@ -172,6 +172,8 @@ protected:
     // limit is big enough)
     void AdjustSpaceLimit();
 
+    // override some base class virtuals
+    virtual bool MSWShouldPreProcessMessage(WXMSG* pMsg);
     virtual wxSize DoGetBestSize() const;
 
 private: