Upgrade libtraceevent to libtraceevent-1.8.4

This project was upgraded with external_updater.
Usage: tools/external_updater/updater.sh update external/libtraceevent
For more info, check https://cs.android.com/android/platform/superproject/main/+/main:tools/external_updater/README.md

Test: TreeHugger
Change-Id: I4ad8a7d530f7002bef095f40c2eeb46a49c883fc