update to libbase-242728

BUG=chromium:331128
TEST=`FEATURES=test emerge-x86-alex platform2` works
TEST=`cbuildbot chromiumos-sdk` works
CQ-DEPEND=CL:185131

Change-Id: Ia03a6ea7aaf6b4ee5d9c512ebf7080c0c28920f1
Reviewed-on: https://chromium-review.googlesource.com/185150
Reviewed-by: Ben Chan <[email protected]>
Commit-Queue: Mike Frysinger <[email protected]>
Tested-by: Mike Frysinger <[email protected]>
22 files changed