Test Predator has given the following results:

Adding a SafeXMLParser to the data-decoder service. by jcivelli@google.com
Suspected changelist touched the crashing line in xml_parser.cc
Suspected changelist touched file(s) in the directory services/data_decoder, which appears in the stack trace.
Suspected changelist touched file xml_parser.cc, which appears in the stack trace.

@jcivelli -- Could you please look into this issue, kindly reassign if it has nothing to do with your changes.

Thank You.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/acc25ce9edc14281e9cc87279816dfecc3e615fa

commit acc25ce9edc14281e9cc87279816dfecc3e615fa
Author: Jay Civelli <jcivelli@google.com>
Date: Mon Dec 04 18:28:43 2017

Fixes for SafeXmlParser choking on DTD and DOCTYPE.

Changing the SafeXmlParser so it ignores nodes like DTDs and processing
instructions.

Bug:  789838 
Change-Id: I0bf4a07509309f9e7720fdcea6283542a0b489ff
Reviewed-on: https://chromium-review.googlesource.com/804946
Reviewed-by: Scott Graham <scottmg@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Jay Civelli <jcivelli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521392}
[modify] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/services/data_decoder/xml_parser.cc
[add] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/services/data_decoder/xml_parser_fuzzer_corpus/input10
[add] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/services/data_decoder/xml_parser_fuzzer_corpus/input11
[add] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/services/data_decoder/xml_parser_fuzzer_corpus/input9
[modify] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/services/data_decoder/xml_parser_unittest.cc
[modify] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/third_party/libxml/chromium/libxml_utils.cc
[modify] https://crrev.com/acc25ce9edc14281e9cc87279816dfecc3e615fa/third_party/libxml/chromium/libxml_utils.h

ClusterFuzz has detected this issue as fixed in range 521363:521398.

Detailed report: https://clusterfuzz.com/testcase?key=5677686331801600

Fuzzer: libFuzzer_xml_parser_fuzzer
Job Type: libfuzzer_chrome_asan_debug
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  root_element.is_none() in xml_parser.cc
  data_decoder::XmlParser::Parse
  xml_parser_fuzzer.cc
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=519803:519843
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=521363:521398

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5677686331801600

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reference.md for more information.

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

ClusterFuzz testcase 5677686331801600 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.