Refactor SetOmahaExperimentLabel out of gcpai and into install_util.

chrome/installer/util/google_chrome_sxs_distribution.cc

Index: chrome/installer/util/google_chrome_sxs_distribution.cc
diff --git a/chrome/installer/util/google_chrome_sxs_distribution.cc b/chrome/installer/util/google_chrome_sxs_distribution.cc
index 157fd74be4280ada3e60e0eef1f9e4c1779ff495..c1c7610ec2100a7d58a0d6e134b0c7cef4b4fc85 100644
--- a/chrome/installer/util/google_chrome_sxs_distribution.cc
+++ b/chrome/installer/util/google_chrome_sxs_distribution.cc
@@ -71,6 +71,10 @@ bool GoogleChromeSxSDistribution::AppHostIsSupported() {
   return false;
 }
 
+bool GoogleChromeSxSDistribution::ShouldSetExperimentLabels() {
+  return true;
+}
+
 string16 GoogleChromeSxSDistribution::ChannelName() {
   return kChannelName;
 }