First CL to try to understand the extent of the cleanup needed in order to remove -Wno-shadow and follow Chromium on enabling this diagnostic. Bug: webrtc:13219 Change-Id: Ie699762da50fe3dbc08b1fd92220962d4b7da86b Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/233641 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org> Cr-Commit-Position: refs/heads/main@{#35134}