Bug 577542 refers to chromeos-mrc/mariadb (Can't find it anymore) but somehow dev-db/mariadb was forced to gcc. Not sure of any connection between the two mariadb packages.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/2a3afdb8f32399b1eacd58b7f9cb2c7cb1599e10

commit 2a3afdb8f32399b1eacd58b7f9cb2c7cb1599e10
Author: Manoj Gupta <manojgupta@google.com>
Date: Fri Nov 03 13:34:58 2017

mariadb: Remove forced build with gcc.

mariadb can be built with clang with latest clang.

BUG= chromium:781062 
TEST=sudo emerge mariadb works.
TEST=emerge-guado_moblab mariadb works.

Change-Id: I8fde0a01b55a37f6f2b5c06f03e768327dd27b05
Reviewed-on: https://chromium-review.googlesource.com/752576
Commit-Ready: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Luis Lozano <llozano@chromium.org>
Reviewed-by: Simran Basi <sbasi@chromium.org>

[rename] https://crrev.com/2a3afdb8f32399b1eacd58b7f9cb2c7cb1599e10/dev-db/mariadb/mariadb-5.5.32-r9.ebuild
[delete] https://crrev.com/fa29b50e1fe7f025204f0490fc1990e44a09e743/chromeos/config/env/dev-db/mariadb