Rename methods for PopupWindow

This CL renames 4 methods for PopupWindow based on API council
suggestions. Also remove unused import in order to `repo upload`

Bug: b/126354063
Test: All ListPopupWindow, MenuPopup and PopupWindow passed
Change-Id: I5db93b1c18a7a3dc9033cb9c5bbe89107ac22024
4 files changed