tools/android/loading Switch the GCE worker to pull queues

tools/android/loading/cloud/backend/google_storage_accessor.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 gcloud import storage
-from oauth2client.client import GoogleCredentials
 
 
 class GoogleStorageAccessor(object):
   """Utility class providing helpers for Google Cloud Storage.
   """
-  def __init__(self, project_name, bucket_name):
+  def __init__(self, credentials, project_name, bucket_name):
     """project_name is the name of the Google Cloud project.
     bucket_name is the name of the bucket that is used for Cloud Storage calls.
     """
-    self._credentials = GoogleCredentials.get_application_default()
+    self._credentials = credentials
     self._project_name = project_name
     self._bucket_name = bucket_name
 
   def _GetStorageClient(self):
     """Returns the storage client associated with the project"""
     return storage.Client(project = self._project_name,
                           credentials = self._credentials)
 
   def _GetStorageBucket(self, storage_client):
     return storage_client.get_bucket(self._bucket_name)
@@ skipping 24 matching lines @@
 
     Returns:
       The URL of the file in Google Cloud Storage.
     """
     client = self._GetStorageClient()
     bucket = self._GetStorageBucket(client)
     blob = bucket.blob(filename_dest)
     blob.upload_from_string(data_string)
     return blob.public_url