New Autofill PERF test that waits for AutofillCallbacks.

Test: mmma -j ./frameworks/base/apct-tests/perftests/core/ &&  \
  adb install -r $OUT/data/app/CorePerfTests/CorePerfTests.apk && \
  adb shell am instrument -w -e class android.view.autofill.AutofillPerfTest \
  com.android.perftests.core/android.support.test.runner.AndroidJUnitRunner

Bug: 38345816

Change-Id: I60c9061b37c7f1f933740657732825e6edbe665f