gpu: Fix broken import path in Maps test

TBR=tonyg@chromium.org, piman@chromium.org
NOTRY=true
BUG=323813

Review URL: https://codereview.chromium.org/101963003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238397 0039d316-1c4b-4281-b951-d872f2087c98

content/test/gpu/gpu_tests/maps.py

@@ -14,7 +14,7 @@ import re
 import maps_expectations
 
 from telemetry import test
-from telemetry.core.backends import bitmap
+from telemetry.core import bitmap
 from telemetry.core import util
 from telemetry.page import page_test
 from telemetry.page import page_set