Add a new 'run_all_unittests' target in base

Make all the places that include run_all_unittests.cc manually depend
on this target instead.

BUG=
TEST=


Review URL: http://codereview.chromium.org/9691067

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@127911 0039d316-1c4b-4281-b951-d872f2087c98
8 files changed