fix(tablet): fix magnification banner in dark mode am: 44660662 am: 05723287 am: bbdcb350

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/21466797



Change-Id: Ideecd82263b6e46fd897b7c90a9a14066009b287
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>