Add missing import for Empty am: 2359071a14 am: f4b3fc8037 am: 2fa8a941df

Original change: https://android-review.googlesource.com/c/platform/tools/test/connectivity/+/1535496

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I062aa676d90a66333eae35469f5054e785a455d3
tree: 661674e1a9c7299b4d09724e1cf0a6633e1c8ffb
  1. acts/
  2. acts_tests/
  3. tools/
  4. wts-acts/
  5. Android.mk
  6. OWNERS
  7. PREUPLOAD.cfg