Add ability to rebaseline skimage to rebaseline.py

Skip pattern matching for skimage, since the skimage results do not
match the pattern.

Automatically fill in expectations_root and actuals_base_url when
--skimage is specified.

Requires a change to move the expectations files to the right place.
Depends on https://codereview.chromium.org/26734006

(SkipBuildBotRuns)

BUG=skia:1466
R=epoger@google.com

Review URL: https://codereview.chromium.org/26666004

git-svn-id: http://skia.googlecode.com/svn/trunk@11717 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/gm_json.py b/gm/gm_json.py
index 0620bca..1d8da9f 100644
--- a/gm/gm_json.py
+++ b/gm/gm_json.py
@@ -13,6 +13,7 @@
 
 # system-level imports
 import json
+import os
 
 
 # Key strings used in GM results JSON files (both expected-results.json and
@@ -82,6 +83,12 @@
 #  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)