Rely on losing focus, not on becoming unfullscreened, to destroy a fullscreen window.

content/browser/renderer_host/render_widget_host_view_gtk.cc

Index: content/browser/renderer_host/render_widget_host_view_gtk.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_gtk.cc b/content/browser/renderer_host/render_widget_host_view_gtk.cc
index c6999c26f79c112fe8d29e036bd98b4c31dcca4c..859ecfff17ea5bb4d366b45081aa981ea3e2414a 100644
--- a/content/browser/renderer_host/render_widget_host_view_gtk.cc
+++ b/content/browser/renderer_host/render_widget_host_view_gtk.cc
@@ -43,6 +43,7 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/x11/WebScreenInfoFactory.h"
 #include "ui/base/gtk/gtk_compat.h"
 #include "ui/base/text/text_elider.h"
+#include "ui/base/x/active_window_watcher_x.h"
 #include "ui/base/x/x11_util.h"
 #include "ui/gfx/gtk_native_view_id_manager.h"
 #include "ui/gfx/gtk_preserve_window.h"
@@ -574,6 +575,7 @@ RenderWidgetHostViewGtk::RenderWidgetHostViewGtk(
       was_imcontext_focused_before_grab_(false),
       do_x_grab_(false),
       is_fullscreen_(false),
+      made_active_(false),

[Daniel Erat, 2012/06/13 19:18:43]

actually, having this variable contain false information unless this is a
fullscreen window makes me nervous.  any reason why you can't register as an
observer in DoSharedInit() and unregister in the d'tor (maybe with another
variable to make sure that you don't unregister unless init was actually
called)?

       destroy_handler_id_(0),
       dragged_at_horizontal_edge_(0),
       dragged_at_vertical_edge_(0),
@@ -659,16 +661,14 @@ void RenderWidgetHostViewGtk::InitAsFullscreen(
   GtkWindow* window = GTK_WINDOW(gtk_window_new(GTK_WINDOW_TOPLEVEL));
   gtk_window_set_decorated(window, FALSE);
   gtk_window_fullscreen(window);
-  g_signal_connect(GTK_WIDGET(window),
-                   "window-state-event",
-                   G_CALLBACK(&OnWindowStateEventThunk),
-                   this);
   destroy_handler_id_ = g_signal_connect(GTK_WIDGET(window),
                                          "destroy",
                                          G_CALLBACK(OnDestroyThunk),
                                          this);
   gtk_container_add(GTK_CONTAINER(window), view_.get());
 
+  ui::ActiveWindowWatcherX::AddObserver(this);
+
   // Try to move and resize the window to cover the screen in case the window
   // manager doesn't support _NET_WM_STATE_FULLSCREEN.
   GdkScreen* screen = gtk_window_get_screen(window);
@@ -766,6 +766,17 @@ bool RenderWidgetHostViewGtk::HasFocus() const {
   return gtk_widget_is_focus(view_.get());
 }
 
+void RenderWidgetHostViewGtk::ActiveWindowChanged(GdkWindow *window) {
+  DCHECK(is_fullscreen_);
+  GdkWindow* our_window = gtk_widget_get_parent_window(view_.get());
+  // If the window was previously active, but isn't active anymore, shut it
+  // down.
+  if (our_window == window)
+    made_active_ = true;
+  else if (made_active_)
+    host_->Shutdown();
+}
+
 bool RenderWidgetHostViewGtk::IsSurfaceAvailableForCopy() const {
   return !!host_->GetBackingStore(false);
 }
@@ -877,8 +888,10 @@ void RenderWidgetHostViewGtk::Destroy() {
     GtkWidget* window = gtk_widget_get_parent(view_.get());
 
     // Disconnect the destroy handler so that we don't try to shutdown twice.
-    if (is_fullscreen_)
+    if (is_fullscreen_) {
       g_signal_handler_disconnect(window, destroy_handler_id_);
+      ui::ActiveWindowWatcherX::RemoveObserver(this);
+    }
 
     gtk_widget_destroy(window);
   }
@@ -951,24 +964,6 @@ gfx::NativeView RenderWidgetHostViewGtk::BuildInputMethodsGtkMenu() {
   return im_context_->BuildInputMethodsGtkMenu();
 }
 
-gboolean RenderWidgetHostViewGtk::OnWindowStateEvent(
-    GtkWidget* widget,
-    GdkEventWindowState* event) {
-  if (is_fullscreen_) {
-    // If a fullscreen widget got unfullscreened (e.g. by the window manager),
-    // close it.
-    bool unfullscreened =
-        (event->changed_mask & GDK_WINDOW_STATE_FULLSCREEN) &&
-        !(event->new_window_state & GDK_WINDOW_STATE_FULLSCREEN);
-    if (unfullscreened) {
-      host_->Shutdown();
-      return TRUE;
-    }
-  }
-
-  return FALSE;
-}
-
 void RenderWidgetHostViewGtk::OnDestroy(GtkWidget* widget) {
   DCHECK(is_fullscreen_);
   host_->Shutdown();