Fixed panel callout widgets showing up in the overview.

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 234adb9c36a89ba571c0283074b0e495b0565712..a92ad02db95a23fa9ef084a525a54f6599b68ade 100644
--- a/ash/wm/panels/panel_layout_manager.cc
+++ b/ash/wm/panels/panel_layout_manager.cc
@@ -258,6 +258,7 @@ PanelLayoutManager::PanelLayoutManager(aura::Window* panel_container)
     : panel_container_(panel_container),
       in_add_window_(false),
       in_layout_(false),
+      show_callout_widgets_(true),
       dragged_panel_(NULL),
       shelf_(NULL),
       shelf_layout_manager_(NULL),
@@ -325,6 +326,13 @@ void PanelLayoutManager::ToggleMinimize(aura::Window* panel) {
     window_state->Minimize();
 }
 
+void PanelLayoutManager::SetShowCalloutWidgets(bool show) {
+  if (show_callout_widgets_ == show)
+    return;
+  show_callout_widgets_ = show;
+  UpdateCallouts();
+}
+
 views::Widget* PanelLayoutManager::GetCalloutWidgetForPanel(
     aura::Window* panel) {
   DCHECK(panel->parent() == panel_container_);
@@ -814,7 +822,7 @@ void PanelLayoutManager::UpdateCallouts() {
         panel->GetTargetBounds());
     gfx::Rect icon_bounds = shelf_->GetScreenBoundsOfItemIconForWindow(panel);
     if (icon_bounds.IsEmpty() || !panel->layer()->GetTargetVisibility() ||
-        panel == dragged_panel_) {
+        panel == dragged_panel_ || !show_callout_widgets_) {
       callout_widget->Hide();
       callout_widget->GetNativeWindow()->layer()->SetOpacity(0);
       continue;