compile failure on chromium/Mac

Builders failed on: 
- Mac: 
  https://build.chromium.org/p/chromium/builders/Mac

First failure:
https://uberchromegw.corp.google.com/i/chromium/builders/Mac/builds/24718

The log includes:

FAILED: test_data/chrome/safe_browsing_dmg/dmg_UDBZ_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDBZ_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UDBZ_SPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDCO_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDCO_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UDCO_SPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRO_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRO_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRO_SPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRW_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRW_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UDRW_SPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDSP_GPTSPUD.sparseimage test_data/chrome/safe_browsing_dmg/dmg_UDSP_NONE.sparseimage test_data/chrome/safe_browsing_dmg/dmg_UDSP_SPUD.sparseimage test_data/chrome/safe_browsing_dmg/dmg_UDTO_GPTSPUD.cdr test_data/chrome/safe_browsing_dmg/dmg_UDTO_NONE.cdr test_data/chrome/safe_browsing_dmg/dmg_UDTO_SPUD.cdr test_data/chrome/safe_browsing_dmg/dmg_UDZO_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UDZO_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UDZO_SPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UFBI_GPTSPUD.dmg test_data/chrome/safe_browsing_dmg/dmg_UFBI_NONE.dmg test_data/chrome/safe_browsing_dmg/dmg_UFBI_SPUD.dmg test_data/chrome/safe_browsing_dmg/hfs_plus.img test_data/chrome/safe_browsing_dmg/hfsx_case_sensitive.img test_data/chrome/safe_browsing_dmg/mach_o_in_dmg.dmg 
python ../../build/gn_run_binary.py ../../chrome/test/data/safe_browsing/dmg/generate_test_data.sh test_data/chrome/safe_browsing_dmg
Volume SafeBrowsingDMG on disk1 failed to unmount: dissented by PID=260 (/usr/libexec/lsd)