added wxTaskBarIcon::IsAvailable

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55991 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/taskbarx11.cpp

@@ -66,7 +66,7 @@
                       wxDEFAULT_FRAME_STYLE | wxFRAME_NO_TASKBAR |
                       wxSIMPLE_BORDER | wxFRAME_SHAPED) {}
 
-        bool IsProtocolSupported() const { return false; }
+        static bool IsProtocolSupported() const { return false; }
     };
 #endif
 
@@ -250,6 +250,15 @@ void wxTaskBarIconArea::OnMenuEvent(wxCommandEvent& event)
     m_icon->ProcessEvent(event);
 }
 
+// ----------------------------------------------------------------------------
+// wxTaskBarIconBase class:
+// ----------------------------------------------------------------------------
+
+bool wxTaskBarIconBase::IsAvailable()
+{
+    return wxTaskBarIconArea::IsProtocolSupported();
+}
+
 // ----------------------------------------------------------------------------
 // wxTaskBarIcon class:
 // ----------------------------------------------------------------------------