1. Moved m_usePrimary to wxClipboardBase as it's now also used by wxMSW/wxMac

2. Added IsUsingPrimarySelection()
3. Fail all clipboard operations when IsUsingPrimarySelection() is true on
   non-X11 platforms


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45183 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/clipbrd.h

@@ -53,11 +53,6 @@ public:
     // clears wxTheClipboard and the system's clipboard if possible
     virtual void Clear();
 
-    // If primary == TRUE, use primary selection in all further ops,
-    // primary == FALSE resets it.
-    virtual void UsePrimarySelection(bool primary = TRUE)
-        { m_usePrimary = primary; }
-
     // implementation from now on
     bool              m_open;
     bool              m_ownsClipboard;
@@ -70,7 +65,6 @@ public:
 
     bool              m_formatSupported;
     GdkAtom           m_targetRequested;
-    bool              m_usePrimary;
     wxDataObject     *m_receivedData;
 
 private: