[ash-md] Added a delay between system menu default/detailed view transitions.

ash/common/system/tray/tray_details_view.cc

Index: ash/common/system/tray/tray_details_view.cc
diff --git a/ash/common/system/tray/tray_details_view.cc b/ash/common/system/tray/tray_details_view.cc
index 9ca7fafd1f6a6578666e87fa161057232dcda5b3..cce297039157698e004ff39d9a2544127af2bdde 100644
--- a/ash/common/system/tray/tray_details_view.cc
+++ b/ash/common/system/tray/tray_details_view.cc
@@ -11,6 +11,7 @@
 #include "ash/common/system/tray/system_tray_item.h"
 #include "ash/common/system/tray/tray_constants.h"
 #include "base/containers/adapters.h"
+#include "base/timer/timer.h"
 #include "third_party/skia/include/core/SkDrawLooper.h"
 #include "ui/compositor/paint_context.h"
 #include "ui/compositor/paint_recorder.h"
@@ -384,18 +385,37 @@ void TrayDetailsView::HandleButtonPressed(views::Button* sender,
 void TrayDetailsView::CreateExtraTitleRowButtons() {}
 
 void TrayDetailsView::TransitionToDefaultView() {
-  // Cache pointer to owner in this function scope. TrayDetailsView will be
-  // deleted after called ShowDefaultView.
-  SystemTrayItem* owner = owner_;
   if (UseMd()) {
     if (back_button_ && back_button_->HasFocus())
-      owner->set_restore_focus(true);
+      owner_->set_restore_focus(true);
   } else {
     if (title_row_ && title_row_->content() &&
         title_row_->content()->HasFocus()) {
-      owner->set_restore_focus(true);
+      owner_->set_restore_focus(true);
     }
+    DoTransitionToDefaultView();
+    return;
+  }
+
+  const int transition_delay =
+      GetTrayConstant(TRAY_POPUP_TRANSITION_TO_DEFAULT_DELAY);
+  if (transition_delay <= 0) {
+    DoTransitionToDefaultView();
+    return;
   }
+
+  transition_delay_timer_.reset(new base::OneShotTimer());
+  transition_delay_timer_->Start(
+      FROM_HERE, base::TimeDelta::FromMilliseconds(transition_delay), this,
+      &TrayDetailsView::DoTransitionToDefaultView);
+}
+
+void TrayDetailsView::DoTransitionToDefaultView() {
+  transition_delay_timer_.reset();
+
+  // Cache pointer to owner in this function scope. TrayDetailsView will be
+  // deleted after called ShowDefaultView.
+  SystemTrayItem* owner = owner_;
   owner->system_tray()->ShowDefaultView(BUBBLE_USE_EXISTING);
   owner->set_restore_focus(false);
 }