Fix python3 issues with gen_fuzzer_owners.py.

cli_output.splitlines() needs a decode('utf-8') now.

Bug: 941669
Change-Id: I8c5241483dac9d77655501aa6e560e679df16dbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2638534
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Abhishek Arya <inferno@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>
Auto-Submit: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Abhishek Arya <inferno@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Cr-Commit-Position: refs/heads/master@{#844971}

testing/libfuzzer/gen_fuzzer_owners.py

@@ -24,7 +24,7 @@ THIRD_PARTY_SEARCH_STRING = 'third_party' + os.sep
 
 def GetAuthorFromGitBlame(blame_output):
   """Return author from git blame output."""
-  for line in blame_output.splitlines():
+  for line in blame_output.decode('utf-8').splitlines():
     m = AUTHOR_REGEX.match(line)
     if m:
       return m.group(1)