Fix NPE in ViewPager.onSaveInstanceState
Fix NPE in ViewPager.onSaveInstanceState

Change-Id: Ifee62477291f970873b5fdeba8336800d1b8643e

androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,aosp-mirror/platform_frameworks_support,AndroidX/androidx,AndroidX/androidx,aosp-mirror/platform_frameworks_support,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,aosp-mirror/platform_frameworks_support,AndroidX/androidx,AndroidX/androidx,aosp-mirror/platform_frameworks_support,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,aosp-mirror/platform_frameworks_support,AndroidX/androidx,androidx/androidx