Enable immersive fullscreen on Windows 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 374 matching lines @@
   observers_.AddObserver(observer);
 }
 
 void ShelfLayoutManager::RemoveObserver(ShelfLayoutManagerObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ShelfLayoutManager, Gesture functions:
 
 void ShelfLayoutManager::OnGestureEdgeSwipe(const ui::GestureEvent& gesture) {

[pkotwicz, 2014/03/18 14:56:47]

Would you be able to replace this entire function with this:

if (visibility_state() == SHELF_AUTO_HIDE) {
  gesture_drag_status_ = GESTURE_DRAG_COMPLETE_IN_PROGRESS;
  gesture_drag_auto_hide_state_ = SHELF_AUTO_HIDE_SHOWN;
  UpdateVisibilityState();
  gesture_drag_status_ = GESTURE_DRAG_DONE;
}

-  // Edge swipe should exit fullscreen, show the tray, and disable auto-hide.
-
-  if (workspace_controller_->GetWindowState() ==
-      WORKSPACE_WINDOW_STATE_FULL_SCREEN) {
-    accelerators::ToggleFullscreen();
+  WorkspaceWindowState window_state(workspace_controller_->GetWindowState());
+  if (window_state == WORKSPACE_WINDOW_STATE_FULL_SCREEN) {
+    const aura::Window* fullscreen_window = GetRootWindowController(
+        root_window_)->GetWindowForFullscreenMode();
+    if (wm::GetWindowState(fullscreen_window)->hide_shelf_when_fullscreen())
+      return;
+  } else if (CalculateShelfVisibility() == SHELF_VISIBLE) {
+    // If the shelf is permanently visible, don't make an effort to display it.
+    return;

[pkotwicz, 2014/03/18 14:56:47]

With the code as you have it, won't you early return if the topmost window is in
immersive fullscreen (thus the shelf is auto hidden) but the shelf was visible
before entering immersive fullscreen?

[zturner, 2014/03/18 18:26:36]

Hmm, the code works in practice.  The relationship between visibility states and
auto hide states is still very confusing to me and the flow isn't very easy to
follow, but the test I've run is:

1) Uncheck the Autohide Shelf checkbox so that we have SHELF_VISIBLE.
2) Press F11 to enter immersive fullscreen.
3) Edge swipe.

The shelf is displayed and the immersive reveal happens, and moving the mouse
hides both.

[pkotwicz, 2014/03/18 19:35:28]

Ahh, I understand. This works because you are checking SHELF_VISIBLE when not
fullscreen.

I believe that the code that I suggested is equivalent and simpler

harrym@ is an expert wrt to the shelf and is conveniently in MTV. He should be
able to explain everyting :)

   }
 
-  ShelfVisibilityState visibility = CalculateShelfVisibility();
-  if (visibility == SHELF_AUTO_HIDE &&
-      CalculateAutoHideState(visibility) == SHELF_AUTO_HIDE_HIDDEN) {
-    SetState(SHELF_VISIBLE);
-    SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_NEVER);
-  }
+  gesture_drag_auto_hide_state_ = SHELF_AUTO_HIDE_SHOWN;
+  gesture_drag_status_ = GESTURE_DRAG_COMPLETE_IN_PROGRESS;
+  SetState(SHELF_AUTO_HIDE);
+  gesture_drag_status_ = GESTURE_DRAG_NONE;
 }
 
 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);
 }
 
@@ skipping 737 matching lines @@
                                                 SHELF_HIDDEN);
     TargetBounds target_bounds;
     CalculateTargetBounds(state_, &target_bounds);
     UpdateBoundsAndOpacity(target_bounds, true, NULL);
     UpdateVisibilityState();
   }
 }
 
 }  // namespace internal
 }  // namespace ash