Merge "Delete Guava 21.0 prebuilt." am: a695d6bb16

Original change: https://android-review.googlesource.com/c/platform/prebuilts/misc/+/2293622

Change-Id: I140f3010d3aaf2e4adc6a65023c3902a2a898ef8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>