git cl + gerrit_util: improve diagnostic logging.

BUG=681704

Change-Id: I1a774350aea901d4e9f2468cff111cbbcd7f3388
Reviewed-on: https://chromium-review.googlesource.com/430794
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
diff --git a/git_cl.py b/git_cl.py
index 1a62794..f18166f 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -5386,7 +5386,10 @@
   def parse_args(self, args=None, values=None):
     options, args = optparse.OptionParser.parse_args(self, args, values)
     levels = [logging.WARNING, logging.INFO, logging.DEBUG]
-    logging.basicConfig(level=levels[min(options.verbose, len(levels) - 1)])
+    logging.basicConfig(
+        level=levels[min(options.verbose, len(levels) - 1)],
+        format='[%(levelname).1s%(asctime)s %(process)d %(thread)d '
+               '%(filename)s] %(message)s')
     return options, args