Fix reference to the new exported symbols file so it works from any build directory, not just when building in 'base'.
Fix reference to the new exported symbols file so it works
from any build directory, not just when building in 'base'.

Make base_unittests explicitly depend on the file so it will
rebuild if we ever change the list of exported symbols.
Review URL: http://codereview.chromium.org/7853

git-svn-id: http://src.chromium.org/svn/trunk/src@3720 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 8e04f686f7e5e6be06fdd231069ee9697c278e32
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser