Use correct string format to get bisect confidence.

tools/bisect-perf-regression.py

 #!/usr/bin/env python
 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Performance Test Bisect Tool
 
 This script bisects a series of changelists using binary search. It starts at
 a bad revision where a performance metric has regressed, and asks for a last
 known-good revision. It will then binary search across this revision range by
@@ skipping 181 matching lines @@
 # The perf dashboard looks for a string like "Estimated Confidence: 95%"
 # to decide whether or not to cc the author(s). If you change this, please
 # update the perf dashboard as well.
 RESULTS_BANNER = """
 ===== BISECT JOB RESULTS =====
 Status: %(status)s
 
 Test Command: %(command)s
 Test Metric: %(metrics)s
 Relative Change: %(change)s
-Estimated Confidence: %(confidence)d%%"""
+Estimated Confidence: %(confidence).02f%%"""
 
 # The perf dashboard specifically looks for the string
 # "Author  : " to parse out who to cc on a bug. If you change the
 # formatting here, please update the perf dashboard as well.
 RESULTS_REVISION_INFO = """
 ===== SUSPECTED CL(s) =====
 Subject : %(subject)s
 Author  : %(author)s%(email_info)s%(commit_info)s
 Commit  : %(cl)s
 Date    : %(cl_date)s"""
@@ skipping 3143 matching lines @@
       # bugs. If you change this, please update the perf dashboard as well.
       bisect_utils.OutputAnnotationStepStart('Results')
     print 'Error: %s' % e.message
     if opts.output_buildbot_annotations:
       bisect_utils.OutputAnnotationStepClosed()
   return 1
 
 
 if __name__ == '__main__':
   sys.exit(main())