This CL converts 7 test classes under com.android.inputmethod.keyboard
to Android Testing Support Library.
This CL also fix missing annotations in KeyboardLayoutTest.
Bug: 110805255
Test: verified as follows. No new test failures.
tapas adb LatinIME LatinIMETests arm64 userdebug && \
DISABLE_PROGUARD=true make -j LatinIME && \
adb install -r $OUT/system/app/LatinIME/LatinIME.apk && \
atest LatinIMETests:com.android.inputmethod.keyboard
Change-Id: I8ab9e3329f159f0df02812fafe44c25efa76c0d1