Update rebaselining tool to auto create new directory if it does not exist.
Update rebaselining tool to auto create new directory if it does not exist.

TEST=rebaselining tool
BUG=none

Review URL: http://codereview.chromium.org/149718

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@20871 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser