[tools] callstats.py: don't retry after many failing results

Change-Id: Ie741a8e4452b6d65ec73bd91ecdea869d7eedc25
BUG: v8:8192
Reviewed-on: https://chromium-review.googlesource.com/1230100
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56011}

tools/callstats.py

@@ -218,7 +218,7 @@ def run_site(site, domain, args, timeout=None):
           # Abort after too many retries, no point in ever increasing the
           # timeout.
           print("TOO MANY EMPTY RESULTS ABORTING RUN")
-          break
+          return
         timeout += 2 ** retries_since_good_run
         retries_since_good_run += 1
         print("EMPTY RESULT, REPEATING RUN ({})".format(