Merge "Prevent position topmost task to top"

            for (int stackNdx = display.getStackCount() - 1; stackNdx >= 0; --stackNdx) {

                final ActivityStack stack = display.getStackAt(stackNdx);

                stack.switchUser(userId);

                Task task = stack.getTopMostTask();

                if (task != null && task != stack) {

                    stack.positionChildAtTop(task);

                }

            }

        }