link undo in main window to editor if the latter has focus (bug #44402) * file-editor.cc (editor_tab_has_focus): helper function checking whether an edit area has the focus; (copyClipboard, pasteClipboard, selectAll): use this helper function; (do_undo): new slot for the undo action triggered from the main window * file-editor.h: new helper function and new slots * main-window.cc (handle_undo_request): emit a signal for undo instead of undoing in terminal window when terminal does not have focus * main-window.h: new undo signal * octave-dock-widget.cc (octave_dock_widget): connect undo signal from main-window to new virtual slot; * octave-dock-widget.h: new virtual slot do_undo, doing nothing

--- a/libgui/src/main-window.h	Sat Mar 14 14:52:58 2015 +0000
+++ b/libgui/src/main-window.h	Sat Mar 14 18:54:23 2015 +0100
@@ -103,6 +103,7 @@
   void copyClipboard_signal (void);
   void pasteClipboard_signal (void);
   void selectAll_signal (void);
+  void undo_signal (void);
 
 public slots: