Fix gpu_tests presubmit error.

content/test/gpu/page_sets/PRESUBMIT.py

 # 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.
 
 import sys
 
 
 def _GetChromiumSrcDir(input_api):
   return input_api.os_path.abspath(input_api.os_path.join(
       input_api.PresubmitLocalPath(), '..', '..', '..', '..'))
 
 
 def LoadSupport(input_api):
   if 'cloud_storage' not in globals():
     # Avoid leaking changes to global sys.path.
     _old_sys_path = sys.path
     try:
       catapult_base_path = input_api.os_path.join(
           _GetChromiumSrcDir(input_api), 'third_party', 'catapult',
           'catapult_base')
       sys.path = [catapult_base_path] + sys.path
-      from catapult_base import cloud_storage
+      from catapult_base import cloud_storage  # pylint: disable=import-error
       globals()['cloud_storage'] = cloud_storage
     finally:
       sys.path = _old_sys_path
 
   return globals()['cloud_storage']
 
 
 def _GetFilesNotInCloud(input_api):
   """Searches for .sha1 files and checks to see if they have already
   been uploaded Cloud Storage. Returns a list of those that have not.
@@ skipping 49 matching lines @@
 
 
 def CheckChangeOnUpload(input_api, output_api):
   results = _VerifyFilesInCloud(input_api, output_api)
   return results
 
 
 def CheckChangeOnCommit(input_api, output_api):
   results = _VerifyFilesInCloud(input_api, output_api)
   return results