adding placeholders for interpolation setting

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67909 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/graphicc.cpp

@@ -368,6 +368,8 @@ public:
 
     virtual bool SetAntialiasMode(wxAntialiasMode antialias);
 
+    virtual bool SetInterpolationQuality(wxInterpolationQuality interpolation);
+
     virtual bool SetCompositionMode(wxCompositionMode op);
 
     virtual void BeginLayer(wxDouble opacity);
@@ -1694,6 +1696,12 @@ bool wxCairoContext::SetAntialiasMode(wxAntialiasMode antialias)
     return true;
 }
 
+bool wxCairoContext::SetInterpolationQuality(wxInterpolationQuality WXUNUSED(interpolation))
+{
+    // placeholder
+    return false;
+}
+
 bool wxCairoContext::SetCompositionMode(wxCompositionMode op)
 {
     if ( m_composition == op )