Upgrade emulator to emu-master-dev build 7209397 am: 4b6976b185 am: fdd1cf8fad am: f2b74cc2d6

Original change: https://android-review.googlesource.com/c/platform/prebuilts/android-emulator/+/1638241

Change-Id: Id632a01bd42d67a598e5efc23f482a0af1444145