Assigning to concern owner from Predator results --
The result is a list of CLs that change the crashed files. 

Author: lukasza
Project: chromium
Changelist: https://chromium.googlesource.com/chromium/src/+/96c9582ab93d94dd07dfe3ff21133082a798728a
Time: Tue Jun 20 02:33:39 2017
Lines 698 of file blink_test_controller.cc which potentially caused crash are changed in this cl (frame #2, "content::BlinkTestController::OnAllServiceWorkersCleared").
Minimum distance from crash line to modified line: 0. (file: blink_test_controller.cc, crashed on: 696, modified: 696).

@lukasza -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

It does seem related to r480692 - I'll try to take a closer look later today or tomorrow.

ClusterFuzz has detected this issue as fixed in range 481568:481626.

Detailed report: https://clusterfuzz.com/testcase?key=6172421530058752

Fuzzer: inferno_twister
Job Type: mac_asan_content_shell
Platform Id: mac

Crash Type: Null-dereference READ
Crash Address: 0x000000000040
Crash State:
  base::debug::TaskAnnotator::RunTask
  base::MessageLoop::RunTask
  base::MessageLoop::DeferOrRunPendingTask
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=mac_asan_content_shell&range=480658:480698
Fixed: https://clusterfuzz.com/revisions?job=mac_asan_content_shell&range=481568:481626

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6172421530058752


See https://dev.chromium.org/Home/chromium-security/bugs/reproducing-clusterfuzz-bugs for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.