Dragging panels near screen edge

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 c4ccd11a3d878a0cd6728166abfa487147f3bfeb..ece898588587dc0ee6a6855d54bffee38454043b 100644
--- a/ash/wm/panels/panel_layout_manager.cc
+++ b/ash/wm/panels/panel_layout_manager.cc
@@ -16,6 +16,7 @@
 #include "ash/wm/frame_painter.h"
 #include "ash/wm/property_util.h"
 #include "ash/wm/window_animations.h"
+#include "ash/wm/window_properties.h"
 #include "ash/wm/window_util.h"
 #include "base/auto_reset.h"
 #include "base/bind.h"
@@ -664,6 +665,7 @@ void PanelLayoutManager::Relayout() {
           ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
       panel_slide_settings.SetTransitionDuration(
           base::TimeDelta::FromMilliseconds(kPanelSlideDurationMilliseconds));
+      visible_panels[i].window->SetProperty(internal::kPanelAttachedKey, true);
       SetChildBoundsDirect(visible_panels[i].window, bounds);
       if (slide_in)
         layer->SetOpacity(1);