Do not show auto-hidden shelf when dragging a window

ash/wm/mru_window_tracker.cc

 // Copyright 2013 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/mru_window_tracker.h"
 
 #include <algorithm>
 
 #include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/window_cycle_list.h"
+#include "ash/wm/window_state.h"
 #include "ash/wm/window_util.h"
 #include "ash/wm/workspace_controller.h"
 #include "ui/aura/client/activation_client.h"
 #include "ui/aura/root_window.h"
 #include "ui/events/event.h"
 #include "ui/events/event_handler.h"
 
 namespace ash {
 
 namespace {
 
 // Adds the windows that can be cycled through for the specified window id to
 // |windows|.
 void AddTrackedWindows(aura::Window* root,
                        int container_id,
                        MruWindowTracker::WindowList* windows) {
   aura::Window* container = Shell::GetContainer(root, container_id);
   const MruWindowTracker::WindowList& children(container->children());
   windows->insert(windows->end(), children.begin(), children.end());
 }
 
+// Adds windows being dragged in the docked container to |windows| list.
+void AddDraggedWindows(aura::Window* root,
+                       MruWindowTracker::WindowList* windows) {
+  aura::Window* container = Shell::GetContainer(
+      root, internal::kShellWindowId_DockedContainer);
+  const MruWindowTracker::WindowList& children = container->children();
+  for (MruWindowTracker::WindowList::const_iterator iter = children.begin();
+       iter != children.end(); ++iter) {
+    if (wm::GetWindowState(*iter)->is_dragged())
+      windows->insert(windows->end(), *iter);
+  }
+}
+
 // Returns true if |window| is a container whose windows can be cycled to.
 bool IsSwitchableContainer(aura::Window* window) {
   if (!window)
     return false;
   for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) {
     if (window->id() == kSwitchableWindowContainerIds[i])
       return true;
   }
   return false;
 }
@@ skipping 22 matching lines @@
       continue;
     for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i)
       AddTrackedWindows(*iter, kSwitchableWindowContainerIds[i], &windows);
   }
 
   // Add windows in the active root windows last so that the topmost window
   // in the active root window becomes the front of the list.
   for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i)
     AddTrackedWindows(active_root, kSwitchableWindowContainerIds[i], &windows);
 
+  // Dragged windows are temporarily parented in docked container. Include them
+  // in the in tracked list.
+  AddDraggedWindows(active_root, &windows);
+
   // Removes unfocusable windows.
   MruWindowTracker::WindowList::iterator last =
       std::remove_if(
           windows.begin(),
           windows.end(),
           std::not1(std::ptr_fun(ash::wm::CanActivateWindow)));
   windows.erase(last, windows.end());
 
   // Put the windows in the mru_windows list at the head, if it's available.
   if (mru_windows) {
@@ skipping 103 matching lines @@
   if (!ignore_window_activations_)
     SetActiveWindow(gained_active);
 }
 
 void MruWindowTracker::OnWindowDestroying(aura::Window* window) {
   mru_windows_.remove(window);
   window->RemoveObserver(this);
 }
 
 }  // namespace ash