Implement "pinned" mode in ash.

ash/shelf/shelf_layout_manager.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/shelf/shelf_layout_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <cstring>
 #include <string>
@@ skipping 295 matching lines @@
 }
 
 void ShelfLayoutManager::UpdateVisibilityState() {
   // Bail out early when there is no |workspace_controller_|, which happens
   // during shutdown after PrepareForShutdown. Also bail before a shelf exists.
   if (!workspace_controller_ || !shelf_widget_->shelf())
     return;
 
   if (state_.is_screen_locked || state_.is_adding_user_screen) {
     SetState(SHELF_VISIBLE);
+  } else if (WmShell::Get()->IsPinned()) {
+    SetState(SHELF_HIDDEN);
   } else {
     // TODO(zelidrag): Verify shelf drag animation still shows on the device
     // when we are in SHELF_AUTO_HIDE_ALWAYS_HIDDEN.
     wm::WorkspaceWindowState window_state(
         workspace_controller_->GetWindowState());
     switch (window_state) {
       case wm::WORKSPACE_WINDOW_STATE_FULL_SCREEN: {
         const aura::Window* fullscreen_window = GetRootWindowController(
             root_window_)->GetWindowForFullscreenMode();
         if (fullscreen_window && wm::GetWindowState(fullscreen_window)->
@@ skipping 216 matching lines @@
 
 void ShelfLayoutManager::OnShelfAlignmentChanged(WmWindow* root_window) {
   if (Shell::GetInstance()->in_mus())
     LayoutShelf();
 }
 
 void ShelfLayoutManager::OnShelfAutoHideBehaviorChanged(WmWindow* root_window) {
   UpdateVisibilityState();
 }
 
+void ShelfLayoutManager::OnPinnedStateChanged(WmWindow* pinned_window) {
+  // Shelf needs to be hidden on entering to pinned mode, or restored
+  // on exiting from pinned mode.
+  UpdateVisibilityState();
+}
+
 void ShelfLayoutManager::OnWindowActivated(
     aura::client::ActivationChangeObserver::ActivationReason reason,
     aura::Window* gained_active,
     aura::Window* lost_active) {
   UpdateAutoHideStateNow();
 }
 
 bool ShelfLayoutManager::IsHorizontalAlignment() const {
   return ::ash::IsHorizontalAlignment(GetAlignment());
 }
@@ skipping 620 matching lines @@
   UpdateBoundsAndOpacity(target_bounds, true, NULL);
   UpdateVisibilityState();
 }
 
 void ShelfLayoutManager::UpdateShelfVisibilityAfterLoginUIChange() {
   UpdateVisibilityState();
   LayoutShelf();
 }
 
 }  // namespace ash