Enable shelf gestures in immersive mode

ash/shelf/shelf_layout_manager.cc

Index: ash/shelf/shelf_layout_manager.cc
diff --git a/ash/shelf/shelf_layout_manager.cc b/ash/shelf/shelf_layout_manager.cc
index a441ab3d1a3ff03c01888a4d925a310ab340ca7c..6d2916ad97cb092d62797551ee92d636540f3bcb 100644
--- a/ash/shelf/shelf_layout_manager.cc
+++ b/ash/shelf/shelf_layout_manager.cc
@@ -296,21 +296,15 @@ void ShelfLayoutManager::UpdateVisibilityState() {
     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());
@@ -440,17 +434,20 @@ void ShelfLayoutManager::CompleteGestureDrag(const ui::GestureEvent& gesture) {
     CancelGestureDrag();
     return;
   }
-
-  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();

[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 (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;
@@ -960,5 +957,18 @@ gfx::Insets ShelfLayoutManager::GetInsetsForAlignment(int distance) const {
   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