Fix bug 175858: [Linux] The panel does not accept keyboard input when it is minimized and expanded

BUG=175858
TEST=Manual test by following the repro steps in the bug


Review URL: https://chromiumcodereview.appspot.com/12223114

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182121 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/gtk/panels/panel_gtk.cc

@@ -823,6 +823,14 @@ void PanelGtk::ClosePanel() {
 
 void PanelGtk::ActivatePanel() {
   gtk_window_present(window_);
+
+  // When the user clicks to expand the minimized panel, the panel has already
+  // become an active window before gtk_window_present is called. Thus the
+  // active window change event, fired by ActiveWindowWatcherXObserver, is not
+  // triggered. We need to call ActiveWindowChanged manually to update panel's
+  // active status. It is OK to call ActiveWindowChanged with the same active
+  // window twice since the 2nd call is just a no-op.
+  ActiveWindowChanged(gtk_widget_get_window(GTK_WIDGET(window_)));
 }
 
 void PanelGtk::DeactivatePanel() {

chrome/browser/ui/gtk/panels/panel_titlebar_gtk.cc

@@ -266,6 +266,7 @@ void PanelTitlebarGtk::OnButtonClicked(GtkWidget* button) {
     panel->OnRestoreButtonClicked(
         (event->button.state & GDK_CONTROL_MASK) ?
             panel::APPLY_TO_ALL : panel::NO_MODIFIER);
+    panel->Activate();
   }
 
   gdk_event_free(event);