base_unittests: Turn down the sleeps on the stats table tests.
base_unittests: Turn down the sleeps on the stats table tests.

These tests are over 20% of the time taken by base_unittests.
I don't think making these sleeps shorter should affect their
reliability too much.

BUG=10611

Review URL: http://codereview.chromium.org/3474009

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@60385 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