Likely the same root cause as  Issue 756959 

ClusterFuzz has detected this issue as fixed in range 495640:495694.

Detailed report: https://clusterfuzz.com/testcase?key=5643861698543616

Fuzzer: ifratric_pdf_generic
Job Type: linux_ubsan_vptr_chrome
Platform Id: linux

Crash Type: Bad-cast
Crash Address: 0x0b3d10e69d20
Crash State:
  Bad-cast to content::ServiceManagerConnection from invalid vptr
  profiling::MemlogClient::~MemlogClient
  ChromeContentClient::~ChromeContentClient
  
Sanitizer: undefined (UBSAN)

Recommended Security Severity: High

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_chrome&range=495503:495507
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_chrome&range=495640:495694

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5643861698543616

See https://github.com/google/clusterfuzz-tools for more information.

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

This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot