Increase rootfs size for amd64 asan builds to 4gb.

TEST=Manual inspection
BUG=chromium:697967
Change-Id: Id7fed2d6c289847534963cbe368b72c1be122b51
Reviewed-on: https://chromium-review.googlesource.com/453921
Commit-Ready: Jacob Dufault <jdufault@chromium.org>
Tested-by: Jacob Dufault <jdufault@chromium.org>
Reviewed-by: Ilja H. Friedel <ihf@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
2 files changed