Add ability to output ImageBaseGSUrl to render_picture and use in rebaseline server.
BUG=skia:2230
R=epoger@google.com
Author: rmistry@google.com
Review URL: https://codereview.chromium.org/479613002
diff --git a/gm/gm_json.py b/gm/gm_json.py
index 1a53997..109bba3 100644
--- a/gm/gm_json.py
+++ b/gm/gm_json.py
@@ -94,6 +94,7 @@
JSONKEY_IMAGE_FILEPATH = 'filepath'
JSONKEY_SOURCE_TILEDIMAGES = 'tiled-images'
JSONKEY_SOURCE_WHOLEIMAGE = 'whole-image'
+JSONKEY_IMAGE_BASE_GS_URL = 'image-base-gs-url'
# Root directory where the buildbots store their actually-generated images...