I encountered the crash when trying to rebaseline for https://chromium-review.googlesource.com/c/529525/.

To reproduce:
1. Create a local branch
2. git cl patch https://chromium-review.googlesource.com/c/529525/ (which has already try results)
3. webkit-patch rebaseline-cl

The above reproduction steps are just for others to reproduce. They are not exactly what I did when encountered the issue. I just used the normal webkit-patch rebaseline-cl process.

Traceback (most recent call last):
  File "/usr/local/google/home/wangxianzhu/chrome/src/third_party/WebKit/Tools/Scripts/webkit-patch", line 84, in <module>
    main()
  File "/usr/local/google/home/wangxianzhu/chrome/src/third_party/WebKit/Tools/Scripts/webkit-patch", line 79, in main
    WebKitPatch(os.path.abspath(__file__)).main()
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/tool/webkit_patch.py", line 116, in main
    result = command.check_arguments_and_execute(options, args, self)
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/tool/commands/command.py", line 110, in check_arguments_and_execute
    return self.execute(options, args, tool) or 0
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/tool/commands/rebaseline_cl.py", line 53, in execute
    jobs = self.latest_try_jobs()
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/tool/commands/rebaseline_cl.py", line 126, in latest_try_jobs
    return self.git_cl().latest_try_jobs(self._try_bots())
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/common/net/git_cl.py", line 107, in latest_try_jobs
    try_results = self.try_job_results()
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/common/net/git_cl.py", line 117, in try_job_results
    return {self._build(r): self._try_job_status(r) for r in raw_results}
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/common/net/git_cl.py", line 117, in <dictcomp>
    return {self._build(r): self._try_job_status(r) for r in raw_results}
  File "/ssd/work/chrome/src/third_party/WebKit/Tools/Scripts/webkitpy/common/net/git_cl.py", line 142, in _build
    build_number = match.group(1)
AttributeError: 'NoneType' object has no attribute 'group'