When double-build-with-Wno-error, add -Wno-error=foo for -Werror=foo

This will gracefully handle cases where a warning enforced with -Werror
got stricter in upstream.

This change also needs updates to golden testdata.  No additional tests
added since this is covered by existing tests.

Originally reviewed in https://android-review.googlesource.com/c/1244796.

BUG=b:149836702
TEST=go test

Change-Id: I94624deb258b15e131387377b99bfb1747dca1a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2079548
Tested-by: Pirama Arumuga Nainar <pirama@google.com>
Reviewed-by: George Burgess <gbiv@chromium.org>
6 files changed