Upgrade emulator to emu-master-dev build 8748233 am: 4ad9d9fb27 am: 2a1a95ce53

Original change: https://googleplex-android-review.googlesource.com/c/platform/prebuilts/android-emulator/+/19014779

Change-Id: Id2c830862c324fd9cc502351edf14c91df08be1b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>