Explicitly keep default constructor in rules without members am: 96af708145 am: e891b3615d

Original change: https://android-review.googlesource.com/c/platform/packages/apps/Messaging/+/3438699

Change-Id: I0d9ba3367e893f5299436eb3c12ad4e86f96cc78
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>