By declaring and defining the flag in a separate and reusable library
it can be used by other main() implementations as well.
Bug: b/237982523
Change-Id: Ia5445ee6e85bc1d536bee2ddd842439f8832116b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/285480
Commit-Queue: Jeremy Leconte <jleconte@google.com>
Auto-Submit: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Jeremy Leconte <jleconte@google.com>
Cr-Commit-Position: refs/heads/main@{#38765}