[luci][realms] use LUCI realms on 20% of builds.

R=ngeoffray

Bug: chromium:1232009
Bug: https://crbug.com/1232009
Change-Id: Id0dca67777b8d363be7ab25df59e2b5d9c1ab54b
diff --git a/tools/luci/config/generated/cr-buildbucket.cfg b/tools/luci/config/generated/cr-buildbucket.cfg
index 5eb8914..3960614 100644
--- a/tools/luci/config/generated/cr-buildbucket.cfg
+++ b/tools/luci/config/generated/cr-buildbucket.cfg
@@ -35,7 +35,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -59,7 +59,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -83,7 +83,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -107,7 +107,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -131,7 +131,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -155,7 +155,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -179,7 +179,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -203,7 +203,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -227,7 +227,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -251,7 +251,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -275,7 +275,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -299,7 +299,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -323,7 +323,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -347,7 +347,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -371,7 +371,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -395,7 +395,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -419,7 +419,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -443,7 +443,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -467,7 +467,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -491,7 +491,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -515,7 +515,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -539,7 +539,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -563,7 +563,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -587,7 +587,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
     builders {
@@ -611,7 +611,7 @@
       service_account: "art-ci-builder@chops-service-accounts.iam.gserviceaccount.com"
       experiments {
         key: "luci.use_realms"
-        value: 0
+        value: 20
       }
     }
   }
diff --git a/tools/luci/config/main.star b/tools/luci/config/main.star
index 4655a44..e5ed70d 100755
--- a/tools/luci/config/main.star
+++ b/tools/luci/config/main.star
@@ -30,7 +30,7 @@
 
 # Launch 0% of Builds in "Realms-aware mode"
 # TODO(tandrii): bump to 100%.
-luci.builder.defaults.experiments.set({"luci.use_realms": 0})
+luci.builder.defaults.experiments.set({"luci.use_realms": 20})
 
 # Tell lucicfg what files it is allowed to touch.
 lucicfg.config(