Cannot force a shown item from an ActionMode into the overflow menu.

1. An app showing an action mode with a visible item that decides to move this item
   to the overflow menu cannot do so since the action menu is not updated properly.
   Specifically, ActionMenuPresenter does not clear the "is action button" property
   of a menu item neither requires nor requests an action button, i.e. the item's
   "show as action" property changed to be never shown on the action bar.

bug:7319766

Change-Id: I5cfda6269466fafca1f039a3bab6397392ae9f17

Author: sganov

core/java/com/android/internal/view/menu/ActionMenuPresenter.java

@@ -476,6 +476,9 @@ public boolean flagActionItems() {
                 if (isAction) maxActions--;
 
                 item.setIsActionButton(isAction);
+            } else {
+                // Neither requires nor requests an action button.
+                item.setIsActionButton(false);
             }
         }
         return true;