Implement "pinned" mode in ash.

ash/shelf/shelf_layout_manager.h

 // Copyright 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.
 
 #ifndef ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 #define ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 137 matching lines @@
 
   // Overridden from SnapLayoutManager:
   void OnWindowResized() override;
   void SetChildBounds(aura::Window* child,
                       const gfx::Rect& requested_bounds) override;
 
   // Overridden from ash::ShellObserver:
   void OnLockStateChanged(bool locked) override;
   void OnShelfAlignmentChanged(WmWindow* root_window) override;
   void OnShelfAutoHideBehaviorChanged(WmWindow* root_window) override;
+  void OnPinnedStateChanged(WmWindow* pinned_window) override;
 
   // Overriden from aura::client::ActivationChangeObserver:
   void OnWindowActivated(
       aura::client::ActivationChangeObserver::ActivationReason reason,
       aura::Window* gained_active,
       aura::Window* lost_active) override;
 
   // Overridden from ash::LockStateObserver:
   void OnLockStateEvent(LockStateObserver::EventType event) override;
 
@@ skipping 55 matching lines @@
     gfx::Rect status_bounds_in_shelf;
     gfx::Insets work_area_insets;
   };
 
   struct State {
     State()
         : visibility_state(SHELF_VISIBLE),
           auto_hide_state(SHELF_AUTO_HIDE_HIDDEN),
           window_state(wm::WORKSPACE_WINDOW_STATE_DEFAULT),
           is_screen_locked(false),
-          is_adding_user_screen(false) {}
+          is_adding_user_screen(false),
+          is_pinned(false) {}
 
     // Returns true if the two states are considered equal. As
     // |auto_hide_state| only matters if |visibility_state| is
     // |SHELF_AUTO_HIDE|, Equals() ignores the |auto_hide_state| as
     // appropriate.
     bool Equals(const State& other) const {
       return other.visibility_state == visibility_state &&
              (visibility_state != SHELF_AUTO_HIDE ||
               other.auto_hide_state == auto_hide_state) &&
              other.window_state == window_state &&
              other.is_screen_locked == is_screen_locked &&
-             other.is_adding_user_screen == is_adding_user_screen;
+             other.is_adding_user_screen == is_adding_user_screen &&
+             other.is_pinned == is_pinned;
     }
 
     ShelfVisibilityState visibility_state;
     ShelfAutoHideState auto_hide_state;
     wm::WorkspaceWindowState window_state;
     bool is_screen_locked;
     bool is_adding_user_screen;
+    bool is_pinned;
   };
 
   // Sets the visibility of the shelf to |state|.
   void SetState(ShelfVisibilityState visibility_state);
 
   // Updates the bounds and opacity of the shelf and status widgets.
   // If |observer| is specified, it will be called back when the animations, if
   // any, are complete.
   void UpdateBoundsAndOpacity(const TargetBounds& target_bounds,
                               bool animate,
@@ skipping 128 matching lines @@
 
   std::unique_ptr<RootWindowControllerObserverImpl>
       root_window_controller_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_LAYOUT_MANAGER_H_