Add panels as a single group of windows per display for overview window cycling.

ash/wm/panels/panel_layout_manager.cc

Index: ash/wm/panels/panel_layout_manager.cc
diff --git a/ash/wm/panels/panel_layout_manager.cc b/ash/wm/panels/panel_layout_manager.cc
index 65f15e69ab1c4bf6daa62374e0cd1eda536f2a24..ea6f9e9cbc3a648d52e6fac349bdebca7d414717 100644
--- a/ash/wm/panels/panel_layout_manager.cc
+++ b/ash/wm/panels/panel_layout_manager.cc
@@ -330,6 +330,15 @@ void PanelLayoutManager::ToggleMinimize(aura::Window* panel) {
   }
 }
 
+views::Widget* PanelLayoutManager::GetCalloutWidgetForPanel(
+    aura::Window* panel) {
+  DCHECK(panel->parent() == panel_container_);
+  PanelList::iterator found =
+      std::find(panel_windows_.begin(), panel_windows_.end(), panel);
+  DCHECK(found != panel_windows_.end());
+  return found->callout_widget;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // PanelLayoutManager, aura::LayoutManager implementation:
 void PanelLayoutManager::OnWindowResized() {
@@ -832,7 +841,8 @@ void PanelLayoutManager::UpdateCallouts() {
     ui::Layer* layer = callout_widget->GetNativeWindow()->layer();
     // If the panel is not over the callout position or has just become visible
     // then fade in the callout.
-    if (distance_until_over_panel > 0 || layer->GetTargetOpacity() < 1) {
+    if ((distance_until_over_panel > 0 || layer->GetTargetOpacity() < 1) &&
+        panel->layer()->GetTargetTransform().IsIdentity()) {
       if (distance_until_over_panel > 0 &&
           slide_distance >= distance_until_over_panel) {
         layer->SetOpacity(0);