[wpr-go] Disable script injection in tools/perf/convert_legacy_wpr_archive

Use '--inject_scripts=', so that the legacy WPR doesn't inject
deterministic.js. Script injection will happen in replay mode when
wpr-go is used.

NOTRY=true # CQ is very flaky and this is a local test script

Bug: 750750
Change-Id: Ie72b3528131483a86c9427201b6c6cc3fc8233ab
Reviewed-on: https://chromium-review.googlesource.com/594658
Commit-Queue: Ned Nguyen <nednguyen@google.com>
Reviewed-by: Ned Nguyen <nednguyen@google.com>
Cr-Commit-Position: refs/heads/master@{#490819}

tools/perf/convert_legacy_wpr_archive

@@ -170,6 +170,7 @@ def main():
         output.write(dump_requests(archive))
       wpr_cmd = [path_util.GetWprDir() + '/replay.py',
                  '--port=8080', '--ssl_port=8089', '--no-dns_forwarding',
+                 '--inject_scripts=',
                  wpr_file]
       print wpr_cmd
       wpr_server = subprocess.Popen(' '.join(wpr_cmd), shell=True)