[ash] Don't remove an item when associated window is dragged

ash/shelf/shelf_window_watcher.cc

Index: ash/shelf/shelf_window_watcher.cc
diff --git a/ash/shelf/shelf_window_watcher.cc b/ash/shelf/shelf_window_watcher.cc
index f177e48c2972680f972251eafcd23e8853c78830..b7b3cfeb2709bb2a2053fe36b03bcc4e316c8f55 100644
--- a/ash/shelf/shelf_window_watcher.cc
+++ b/ash/shelf/shelf_window_watcher.cc
@@ -146,18 +146,18 @@ void ShelfWindowWatcher::OnWindowAdded(aura::Window* window) {
 }
 
 void ShelfWindowWatcher::OnWillRemoveWindow(aura::Window* window) {
-  // Remove a child window of default container and its item if it has.
+  // Remove a child window of default container.
   if (observed_windows_.IsObserving(window))

[sky, 2013/12/12 16:41:43]

If you do this, it means you need to better track window. In particular if
window gets added to another container it should not still have an item on the
shelf. Also, there should be a way for you to detect the window is in the
process of being dragged and only special case that.

[simonhong, 2013/12/13 02:03:45]

Checked window's dragging state and if so, an item is not removed.

     observed_windows_.Remove(window);
-
-  if (HasLauncherItemForWindow(window))
-    RemoveLauncherItem(window);
 }
 
 void ShelfWindowWatcher::OnWindowDestroying(aura::Window* window) {
   // Remove the default container.
   if (observed_windows_.IsObserving(window))
     observed_windows_.Remove(window);
+
+  if (HasLauncherItemForWindow(window))
+    RemoveLauncherItem(window);
 }
 
 void ShelfWindowWatcher::OnWindowPropertyChanged(aura::Window* window,