Fix inconsistent FieldTrial group assignment due to float errors.
This was discovered by the InstantExtended field trial that was
using very small group percentages and discovered several groups
of the same size were getting different user counts.
BUG=290438
TEST=New unit test that fails without the fix.
Review URL: https://chromiumcodereview.appspot.com/23710041
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@224011 0039d316-1c4b-4281-b951-d872f2087c98
CrOS-Libchrome-Original-Commit: 73078c450d7604ed63beeab514a66c3c020ec703
3 files changed