Enable shelf gestures in immersive mode

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 "ash/ash_switches.h"
@@ skipping 278 matching lines @@
   if (Shell::GetInstance()->session_state_delegate()->IsScreenLocked()) {
     SetState(SHELF_VISIBLE);
   } else if (gesture_drag_status_ == GESTURE_DRAG_COMPLETE_IN_PROGRESS) {
     // TODO(zelidrag): Verify shelf drag animation still shows on the device
     // when we are in SHELF_AUTO_HIDE_ALWAYS_HIDDEN.
     SetState(CalculateShelfVisibilityWhileDragging());
   } else {
     WorkspaceWindowState window_state(workspace_controller_->GetWindowState());
     switch (window_state) {
       case WORKSPACE_WINDOW_STATE_FULL_SCREEN:
-      {
-        aura::Window* fullscreen_window =
-            GetRootWindowController(root_window_)->GetFullscreenWindow();
-        if (fullscreen_window->GetProperty(kFullscreenUsesMinimalChromeKey)) {
-          DCHECK_NE(auto_hide_behavior_, SHELF_AUTO_HIDE_ALWAYS_HIDDEN);
+        if (IsInImmersiveMode()) {
           SetState(SHELF_AUTO_HIDE);
         } else {
           SetState(SHELF_HIDDEN);
         }
         break;
-      }
       case WORKSPACE_WINDOW_STATE_MAXIMIZED:
         SetState(CalculateShelfVisibility());
         break;
-
       case WORKSPACE_WINDOW_STATE_WINDOW_OVERLAPS_SHELF:
       case WORKSPACE_WINDOW_STATE_DEFAULT:
         SetState(CalculateShelfVisibility());
         SetWindowOverlapsShelf(window_state ==
                                WORKSPACE_WINDOW_STATE_WINDOW_OVERLAPS_SHELF);
         break;
     }
   }
 }
 
@@ skipping 109 matching lines @@
           gesture.details().velocity_y() > 0);
     }
   } else {
     NOTREACHED();
   }
 
   if (!should_change) {
     CancelGestureDrag();
     return;
   }
-
+  if (shelf_)
+    shelf_->Deactivate();
+  shelf_->status_area_widget()->Deactivate();

[James Cook, 2013/05/22 12:04:22]

Won't this line crash is shelf_ is NULL?  Either you need to put this into the
condition above, or the if() above isn't needed.

[rharrison, 2013/05/22 20:20:02]

Done.

   gesture_drag_auto_hide_state_ =
       gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN ?
       SHELF_AUTO_HIDE_HIDDEN : SHELF_AUTO_HIDE_SHOWN;
-  if (shelf_)
-    shelf_->Deactivate();
-  shelf_->status_area_widget()->Deactivate();
   if (gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_HIDDEN &&
       auto_hide_behavior_ != SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS) {
     gesture_drag_status_ = GESTURE_DRAG_NONE;
-    SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS);
+    if (!IsInImmersiveMode()) {
+      SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS);
+    } else {
+      UpdateVisibilityState();
+    }
   } else if (gesture_drag_auto_hide_state_ == SHELF_AUTO_HIDE_SHOWN &&
              auto_hide_behavior_ != SHELF_AUTO_HIDE_BEHAVIOR_NEVER) {
     gesture_drag_status_ = GESTURE_DRAG_NONE;
     SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_NEVER);
   } else {
     gesture_drag_status_ = GESTURE_DRAG_COMPLETE_IN_PROGRESS;
     UpdateVisibilityState();
     gesture_drag_status_ = GESTURE_DRAG_NONE;
   }
   LayoutShelf();
@@ skipping 489 matching lines @@
       return gfx::Insets(0, 0, 0, distance);
     case SHELF_ALIGNMENT_RIGHT:
       return gfx::Insets(0, distance, 0, 0);
     case SHELF_ALIGNMENT_TOP:
       return gfx::Insets(0, 0, distance, 0);
   }
   NOTREACHED();
   return gfx::Insets();
 }
 
+bool ShelfLayoutManager::IsInImmersiveMode() const {
+  RootWindowController* controller = GetRootWindowController(root_window_);
+  if (!controller)
+    return false;
+  aura::Window* window = controller->GetFullscreenWindow();
+  if (!window)
+    return false;
+  if (!window->GetProperty(kFullscreenUsesMinimalChromeKey))
+    return false;
+  return true;
+}
+
+
 }  // namespace internal
 }  // namespace ash