Move full-screen detection logic from PanelManager to DisplaySettingsProvider.

chrome/browser/ui/panels/base_panel_browser_test.cc

Index: chrome/browser/ui/panels/base_panel_browser_test.cc
diff --git a/chrome/browser/ui/panels/base_panel_browser_test.cc b/chrome/browser/ui/panels/base_panel_browser_test.cc
index c67a59057ad73bcf03e4422c7fc7b6b11bbbdf6e..79f5b60b072806c6b2c975542aecb1d87e3be3a4 100644
--- a/chrome/browser/ui/panels/base_panel_browser_test.cc
+++ b/chrome/browser/ui/panels/base_panel_browser_test.cc
@@ -89,8 +89,22 @@ MockDisplaySettingsProviderImpl::MockDisplaySettingsProviderImpl(
     PanelManager* panel_manager) {
   DisplaySettingsProvider* old_provider =
       panel_manager->display_settings_provider();
-  set_display_area_observer(old_provider->display_area_observer());
-  set_desktop_bar_observer(old_provider->desktop_bar_observer());
+
+  ObserverListBase<DisplaySettingsProvider::DisplayAreaObserver>::Iterator
+      display_area_observers_iter(old_provider->display_area_observers());
+  AddDisplayAreaObserver(display_area_observers_iter.GetNext());
+  DCHECK(!display_area_observers_iter.GetNext());
+
+  ObserverListBase<DisplaySettingsProvider::DesktopBarObserver>::Iterator
+      desktop_bar_observer_iter(old_provider->desktop_bar_observers());
+  AddDesktopBarObserver(desktop_bar_observer_iter.GetNext());
+  DCHECK(!desktop_bar_observer_iter.GetNext());
+
+  ObserverListBase<DisplaySettingsProvider::FullScreenObserver>::Iterator
+      full_screen_observer_iter(old_provider->full_screen_observers());
+  AddFullScreenObserver(full_screen_observer_iter.GetNext());
+  DCHECK(!full_screen_observer_iter.GetNext());
+
   panel_manager->set_display_settings_provider(this);
 
   memset(mock_desktop_bars, 0, sizeof(mock_desktop_bars));