better system for managing kbd focus after cmd-w closing a dialog.

Key, Button and Focus In events in the editor+mixer windows cause the respective window to be noted
as the window to which focus should return after a dialog is closed with cmd/ctrl-w

gtk2_ardour/ardour_ui_ed.cc

@@ -87,6 +87,7 @@ ARDOUR_UI::create_editor ()
 
 	editor->Realized.connect (sigc::mem_fun (*this, &ARDOUR_UI::editor_realized));
 	editor->signal_window_state_event().connect (sigc::bind (sigc::mem_fun (*this, &ARDOUR_UI::main_window_state_event_handler), true));
+        editor->signal_event().connect (sigc::bind (sigc::ptr_fun (&Keyboard::catch_user_event_for_pre_dialog_focus), editor));
 
 	return 0;
 }

gtk2_ardour/ardour_ui_mixer.cc

@@ -23,6 +23,8 @@
    is to cut down on the nasty compile times for these classes.
 */
 
+#include "gtkmm2ext/keyboard.h"
+
 #include "actions.h"
 #include "ardour_ui.h"
 #include "mixer_ui.h"
@@ -46,6 +48,7 @@ ARDOUR_UI::create_mixer ()
 	}
 
 	mixer->signal_window_state_event().connect (sigc::bind (sigc::mem_fun (*this, &ARDOUR_UI::main_window_state_event_handler), false));
+        mixer->signal_event().connect (sigc::bind (sigc::ptr_fun (&Gtkmm2ext::Keyboard::catch_user_event_for_pre_dialog_focus), mixer));
 
 	return 0;
 }

libs/gtkmm2ext/gtkmm2ext/keyboard.h

@@ -166,6 +166,8 @@ class LIBGTKMM2EXT_API Keyboard : public sigc::trackable, PBD::Stateful
 	static std::string current_binding_name () { return _current_binding_name; }
 	static std::map<std::string,std::string> binding_files;
 
+        static bool catch_user_event_for_pre_dialog_focus (GdkEvent* ev, Gtk::Window* w);
+
 	int reset_bindings ();
 
 	struct AccelKeyLess {
@@ -211,6 +213,7 @@ class LIBGTKMM2EXT_API Keyboard : public sigc::trackable, PBD::Stateful
 	static void set_modifier (uint32_t newval, uint32_t& variable);
 
 	static bool _some_magic_widget_has_focus;
+        static Gtk::Window* pre_dialog_active_window;
 };
 
 } /* namespace */

libs/gtkmm2ext/keyboard.cc

@@ -111,9 +111,9 @@ bool Keyboard::bindings_changed_after_save_became_legal = false;
 map<string,string> Keyboard::binding_files;
 string Keyboard::_current_binding_name;
 map<AccelKey,pair<string,string>,Keyboard::AccelKeyLess> Keyboard::release_keys;
+Gtk::Window* Keyboard::pre_dialog_active_window = 0;
 
 /* set this to initially contain the modifiers we care about, then track changes in ::set_edit_modifier() etc. */
-
 GdkModifierType Keyboard::RelevantModifierKeyMask;
 
 void
@@ -432,17 +432,37 @@ Keyboard::close_current_dialog ()
 	if (current_window) {
 		current_window->hide ();
 		current_window = 0;
-#ifdef __APPLE__
-		/* Since Apple users has a basically unconfigurable window
-		   manager, and since users there cannot use
-		   focus-follows-mouse, we force focus back to some application
-		   "main window" after closing a dialog via Primary-w.
-		*/
-		GrabFocus ();
-#endif
+
+                if (pre_dialog_active_window) {
+                        pre_dialog_active_window->present ();
+                        pre_dialog_active_window = 0;
+                }
 	}
 }
 
+bool
+Keyboard::catch_user_event_for_pre_dialog_focus (GdkEvent* ev, Gtk::Window* w)
+{
+        switch (ev->type) {
+        case GDK_BUTTON_PRESS:
+        case GDK_BUTTON_RELEASE:
+        case GDK_KEY_PRESS:
+        case GDK_KEY_RELEASE:
+                pre_dialog_active_window = w;
+                break;
+
+        case GDK_FOCUS_CHANGE:
+                if (ev->focus_change.in) {
+                        pre_dialog_active_window = w;
+                }
+                break;
+
+        default:
+                break;
+        }
+        return false;
+}
+
 bool
 Keyboard::key_is_down (uint32_t keyval)
 {