Let build-bisect.py print download progress.
Let build-bisect.py print download progress.

BUG=None
TEST=run build-bisect.py while riding the shuttle, feel reassured by progress bar

Review URL: http://codereview.chromium.org/6024005

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@69723 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