cros: Fix mouse over-scroll animation not happening.

ash/wm/app_list_controller.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/wm/app_list_controller.h"
 
 #include "ash/launcher/launcher.h"
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
@@ skipping 320 matching lines @@
 void AppListController::TransitionChanged() {
   // |view_| could be NULL when app list is closed with a running transition.
   if (!view_)
     return;
 
   const app_list::PaginationModel::Transition& transition =
       pagination_model_->transition();
   if (pagination_model_->is_valid_page(transition.target_page))
     return;
 
-  if (pagination_model_->scrolling()) {
+  if (!pagination_model_->IsRevertingCurrentTransition()) {
     const int current_page = pagination_model_->selected_page();
     const int dir = transition.target_page > current_page ? -1 : 1;
 
     const double progress = 1.0 - pow(1.0 - transition.progress, 4);
     const int shift = kMaxOverScrollShift * progress * dir;
 
     gfx::Rect shifted(view_bounds_);
     shifted.set_x(shifted.x() + shift);
     view_->GetWidget()->SetBounds(shifted);
     should_snap_back_ = true;
   } else if (should_snap_back_) {
     should_snap_back_ = false;
     ui::Layer* layer = GetLayer(view_->GetWidget());
     ui::ScopedLayerAnimationSettings animation(layer->GetAnimator());
     animation.SetTransitionDuration(
         base::TimeDelta::FromMilliseconds(kSnapBackAnimationDurationMs));
     layer->SetBounds(view_bounds_);
   }
 }
 
 }  // namespace internal
 }  // namespace ash