Fully support the autohide shelf option for touch UI on Windows.

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 371 matching lines @@
 
 void ShelfLayoutManager::AddObserver(ShelfLayoutManagerObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void ShelfLayoutManager::RemoveObserver(ShelfLayoutManagerObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-// ShelfLayoutManager, Gesture dragging:
+// ShelfLayoutManager, Gesture functions:
+
+#if defined(OS_WIN)
+void ShelfLayoutManager::OnGestureEdgeSwipe(const ui::GestureEvent& gesture) {
+  // Edge swipe should exit fullscreen, show the tray, and disable auto-hide.
+
+  if (workspace_controller_->GetWindowState() ==
+      WORKSPACE_WINDOW_STATE_FULL_SCREEN) {
+    const std::vector<aura::Window*> windows =
+        ash::MruWindowTracker::BuildWindowList(false);
+
+    for (size_t i = 0; i < windows.size(); ++i) {
+      if (windows[i] && windows[i]->IsVisible() &&
+          root_window_ == windows[i]->GetRootWindow()) {
+        wm::WindowState* window_state = wm::GetWindowState(windows[i]);
+        if (window_state->IsFullscreen())
+          window_state->ToggleFullscreen();
+      }
+    }
+  }
+
+  ShelfVisibilityState visibility = CalculateShelfVisibility();
+  if (visibility == SHELF_AUTO_HIDE &&
+      CalculateAutoHideState(visibility) == SHELF_AUTO_HIDE_HIDDEN) {
+    SetState(SHELF_VISIBLE);
+    SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_NEVER);
+  }
+}
+#endif
 
 void ShelfLayoutManager::StartGestureDrag(const ui::GestureEvent& gesture) {
   gesture_drag_status_ = GESTURE_DRAG_IN_PROGRESS;
   gesture_drag_amount_ = 0.f;
   gesture_drag_auto_hide_state_ = visibility_state() == SHELF_AUTO_HIDE ?
       auto_hide_state() : SHELF_AUTO_HIDE_SHOWN;
   UpdateShelfBackground(BACKGROUND_CHANGE_ANIMATE);
 }
 
 ShelfLayoutManager::DragState ShelfLayoutManager::UpdateGestureDrag(
@@ skipping 747 matching lines @@
       return gfx::Insets(0, distance, 0, 0);
     case SHELF_ALIGNMENT_TOP:
       return gfx::Insets(0, 0, distance, 0);
   }
   NOTREACHED();
   return gfx::Insets();
 }
 
 }  // namespace internal
 }  // namespace ash