First kotlin

Convert one class to kotlin and provide a slight amount of guidance.

Test: existing tests
Change-Id: Ie8659765b674ac7b2d82ed3d343f387195c07d83

diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index ae42882..fbbc2a3 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg

@@ -15,3 +15,5 @@
 strings_lint_hook = ${REPO_ROOT}/frameworks/base/tools/stringslint/stringslint_sha.sh ${PREUPLOAD_COMMIT}
 
 hidden_api_txt_hook = ${REPO_ROOT}/frameworks/base/tools/hiddenapi/checksorted_sha.sh ${PREUPLOAD_COMMIT} ${REPO_ROOT}
+
+ktlint_hook = ${REPO_ROOT}/prebuilts/ktlint/ktlint.py -f ${PREUPLOAD_FILES}