rebaseline.py: add --add-new option, and only add new expectations if it is set

R=senorblanco@chromium.org

Review URL: https://codereview.chromium.org/16363006

git-svn-id: http://skia.googlecode.com/svn/trunk@9527 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tools/tests/run.sh b/tools/tests/run.sh
index 6d52c65..337e883d 100755
--- a/tools/tests/run.sh
+++ b/tools/tests/run.sh
@@ -212,5 +212,6 @@
 rebaseline_test "--tests test1 test2 --configs 565 8888 --subdirs base-android-galaxy-nexus base-shuttle-win7-intel-float" "$REBASELINE_OUTPUT/subset"
 rebaseline_test "--tests test1 test2" "$REBASELINE_OUTPUT/all"
 rebaseline_test "--json-base-url file:$REBASELINE_INPUT/json1 --subdirs base-android-galaxy-nexus base-shuttle-win7-intel-float" "$REBASELINE_OUTPUT/using-json1"
+rebaseline_test "--json-base-url file:$REBASELINE_INPUT/json1 --subdirs base-android-galaxy-nexus base-shuttle-win7-intel-float --add-new" "$REBASELINE_OUTPUT/using-json1-add-new"
 
 echo "All tests passed."