Don't assume that httplib2 responses contain any preset attributes, s…

…ince they are looked up dynamically from a response headers dict. Fixes googleapis#93

gcloud/storage/exceptions.py

@@ -14,7 +14,7 @@ def __init__(self, response, content):
 class NotFoundError(ConnectionError):
 
   def __init__(self, response, content):
-    self.message = 'GET %s returned a 404.' % (response.url)
+    self.message = 'Request returned a 404. Headers: %s' % (response)
 
 
 class StorageDataError(StorageError):

gcloud/storage/test_connection.py

@@ -1,10 +1,19 @@
 import unittest2
 
 from gcloud.storage.connection import Connection
-
+from gcloud.storage.exceptions import NotFoundError
 
 class TestConnection(unittest2.TestCase):
 
   def test_init(self):
     connection = Connection('project-name')
     self.assertEqual('project-name', connection.project)
+
+
+class TestExceptions(unittest2.TestCase):
+
+  def test_not_found_always_prints(self):
+    e = NotFoundError({}, None)
+    self.assertEqual('', str(e))
+
+