Add ability to rebaseline skimage to rebaseline.py

gm/gm_json.py

Index: gm/gm_json.py
diff --git a/gm/gm_json.py b/gm/gm_json.py
index 0620bca4102a831246fbfea417a56b552f1fb4b9..1d8da9f12799af8621bb72c1642e94b4695faa01 100644
--- a/gm/gm_json.py
+++ b/gm/gm_json.py
@@ -13,6 +13,7 @@ __author__ = 'Elliot Poger'
 
 # system-level imports
 import json
+import os
 
 
 # Key strings used in GM results JSON files (both expected-results.json and
@@ -82,6 +83,12 @@ GM_ACTUALS_ROOT_HTTP_URL = (
 #  as a GS URL that allows credential-protected write access:
 GM_ACTUALS_ROOT_GS_URL = 'gs://chromium-skia-gm/gm'
 
+# Root directory where buildbots store skimage actual results json files.
+SKIMAGE_ACTUALS_BASE_URL = (
+    'http://chromium-skia-gm.commondatastorage.googleapis.com/skimage/actuals')
+# Root directory inside trunk where skimage expectations are stored.
+SKIMAGE_EXPECTATIONS_ROOT = os.path.join('expectations', 'skimage')
+
 # Pattern used to assemble each image's filename
 IMAGE_FILENAME_PATTERN = '(\S+)_(\S+)\.png'  # matches (testname, config)