UMA data collection for docked windows

ash/wm/dock/docked_window_layout_manager.h

 // Copyright (c) 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.
 
 #ifndef ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_
 #define ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_layout_manager_observer.h"
 #include "ash/shell_observer.h"
@@ skipping 27 matching lines @@
 
 namespace ash {
 class Launcher;
 
 namespace internal {
 class DockedWindowLayoutManagerObserver;
 class DockedWindowResizerTest;
 class ShelfLayoutManager;
 class WorkspaceController;
 
+// User action recorded for use in UMA histograms.
+enum DockedAction {
+  DOCKED_ACTION_CANCEL,     // Dragged into or out of dock but cancelled.
+  DOCKED_ACTION_DOCK,       // Dragged and docked a window.
+  DOCKED_ACTION_UNDOCK,     // Dragged and undocked a window.
+  DOCKED_ACTION_RESIZE,     // Resized a docked window.
+  DOCKED_ACTION_REORDER,    // Reordered docked windows.
+  DOCKED_ACTION_EVICT,      // A docked window could not stay docked.
+  DOCKED_ACTION_MAXIMIZE,   // Maximized a docked window.
+  DOCKED_ACTION_MINIMIZE,   // Minimized a docked window.
+  DOCKED_ACTION_RESTORE,    // Restored a docked window that was minimized.
+  DOCKED_ACTION_CLOSE,      // Closed a window while it was docked.
+  DOCKED_ACTION_COUNT,      // Maximum value of this enum for histograms use.
+};
+
 struct WindowWithHeight {
   explicit WindowWithHeight(aura::Window* window) :
     window_(window),
     height_(window->bounds().height()) { }
   aura::Window* window() { return window_; }
   const aura::Window* window() const { return window_; }
   aura::Window* window_;
   int height_;
 };
 
@@ skipping 202 matching lines @@
   // Target bounds of a docked window being dragged.
   gfx::Rect dragged_bounds_;
 
   // Side of the screen that the dock is positioned at.
   DockedAlignment alignment_;
 
   // The last active window. Used to maintain stacking order even if no windows
   // are currently focused.
   aura::Window* last_active_window_;
 
+  // Number of windows that were docked last time when a window was docked or
+  // undocked.
+  int previous_docked_windows_;
+
   // Widget used to paint a background for the docked area.
   scoped_ptr<views::Widget> background_widget_;
 
   // Observers of dock bounds changes.
   ObserverList<DockedWindowLayoutManagerObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(DockedWindowLayoutManager);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_