Suppress thread-safety analysis Clang recently expanded its thread safety analysis to check more things by default. Angle doesn't have the annotations to support it, so make sure the flag isn't passed or else we'll get warnings. Bug: chromium:430317494 Change-Id: I39ea40bcc0023cdf08086ab97577c57a491ac767 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6716457 Auto-Submit: Devon Loehr <dloehr@google.com> Reviewed-by: Amirali Abdolrashidi <abdolrashidi@google.com> Reviewed-by: Yuxin Hu <yuxinhu@google.com> Commit-Queue: Amirali Abdolrashidi <abdolrashidi@google.com>