Tracing: fix error checking from deflate() when compressing trace

tools/perf/core/about_tracing_integration_test.py

 # Copyright 2016 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.
 from telemetry import decorators
 from telemetry.testing import tab_test_case
 
 
 class AboutTracingIntegrationTest(tab_test_case.TabTestCase):
 
   @decorators.Disabled('android',
-                       'mac',  # Flaky, see crbug.com/632238.
-                       'win')  # crbug.com/630030
+                       'win')  # https://crbug.com/632871
   def testBasicTraceRecording(self):
     action_runner = self._tab.action_runner
     action_runner.Navigate('chrome://tracing')
 
     # Click 'record' to trigger record selection diaglog.
     action_runner.WaitForElement(selector='#record-button')
     action_runner.ClickElement(selector='#record-button')
 
     # Wait for record selection diaglog to pop up, then click record.
     action_runner.WaitForElement(selector='.overlay')
     action_runner.ClickElement(
         element_function=("document.querySelector('.overlay').shadowRoot."
                           "querySelectorAll('button')[0]"))
 
     # Stop recording after 1 seconds.
     action_runner.Wait(1)
     action_runner.ClickElement(
         element_function=
         "document.querySelector('.overlay').querySelector('button')")
 
     # Make sure that we can see the browser track.
     action_runner.WaitForElement(selector='div[title~="Browser"]')