Clean up references to obsolete experiments.

Release-Notes: skip
Change-Id: Ia01271fb883c7bd9bd9320c14a62d4b3c6c8f969

java/com/google/gerrit/server/experiments/ExperimentFeaturesConstants.java

diff --git a/java/com/google/gerrit/server/experiments/ExperimentFeaturesConstants.java b/java/com/google/gerrit/server/experiments/ExperimentFeaturesConstants.java
index 5a4580c..32ec401 100644
--- a/java/com/google/gerrit/server/experiments/ExperimentFeaturesConstants.java
+++ b/java/com/google/gerrit/server/experiments/ExperimentFeaturesConstants.java
@@ -20,14 +20,9 @@
 public class ExperimentFeaturesConstants {
 
   /** Features that are known experiments and can be referenced in the code. */
-  public static String UI_FEATURE_PATCHSET_COMMENTS = "UiFeature__patchset_comments";
-
-  public static String UI_FEATURE_SUBMIT_REQUIREMENTS_UI = "UiFeature__submit_requirements_ui";
-
   public static String GERRIT_BACKEND_FEATURE_ATTACH_NONCE_TO_DOCUMENTATION =
       "GerritBackendFeature__attach_nonce_to_documentation";
 
   /** Features, enabled by default in the current release. */
-  public static final ImmutableSet<String> DEFAULT_ENABLED_FEATURES =
-      ImmutableSet.of(UI_FEATURE_PATCHSET_COMMENTS, UI_FEATURE_SUBMIT_REQUIREMENTS_UI);
+  public static final ImmutableSet<String> DEFAULT_ENABLED_FEATURES = ImmutableSet.of();
 }

javatests/com/google/gerrit/acceptance/server/experiments/ExperimentFeaturesIT.java

diff --git a/javatests/com/google/gerrit/acceptance/server/experiments/ExperimentFeaturesIT.java b/javatests/com/google/gerrit/acceptance/server/experiments/ExperimentFeaturesIT.java
index b2a0ded..e011ffc 100644
--- a/javatests/com/google/gerrit/acceptance/server/experiments/ExperimentFeaturesIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/experiments/ExperimentFeaturesIT.java
@@ -68,10 +68,7 @@
       values = {"UiFeature__patchset_comments", "UiFeature__submit_requirements_ui"})
   public void configOverride_defaultFeatureDisabled() {
     assertThat(experimentFeatures.isFeatureEnabled("enabledFeature")).isTrue();
-    assertThat(
-            experimentFeatures.isFeatureEnabled(
-                ExperimentFeaturesConstants.UI_FEATURE_PATCHSET_COMMENTS))
-        .isFalse();
+    assertThat(experimentFeatures.isFeatureEnabled("UiFeature__patchset_comments")).isFalse();
     assertThat(experimentFeatures.getEnabledExperimentFeatures()).containsExactly("enabledFeature");
   }
 }

javatests/com/google/gerrit/httpd/raw/IndexServletTest.java

diff --git a/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java b/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
index f65e823..06ea8b6 100644
--- a/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
+++ b/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
@@ -60,15 +60,13 @@
     String testCdnPath = "bar-cdn";
     String testFaviconURL = "zaz-url";
 
-    // Pick any known experiment enabled by default;
-    String disabledDefault = ExperimentFeaturesConstants.UI_FEATURE_PATCHSET_COMMENTS;
-    assertThat(ExperimentFeaturesConstants.DEFAULT_ENABLED_FEATURES).contains(disabledDefault);
+    assertThat(ExperimentFeaturesConstants.DEFAULT_ENABLED_FEATURES).isEmpty();
 
     org.eclipse.jgit.lib.Config serverConfig = new org.eclipse.jgit.lib.Config();
     serverConfig.setStringList(
         "experiments", null, "enabled", ImmutableList.of("NewFeature", "DisabledFeature"));
     serverConfig.setStringList(
-        "experiments", null, "disabled", ImmutableList.of("DisabledFeature", disabledDefault));
+        "experiments", null, "disabled", ImmutableList.of("DisabledFeature"));
     ExperimentFeatures experimentFeatures = new ConfigExperimentFeatures(serverConfig);
     IndexServlet servlet =
         new IndexServlet(
@@ -97,7 +95,6 @@
                 + "\\x5b\\x5d\\x7d');");
     ImmutableSet<String> enabledDefaults =
         ExperimentFeaturesConstants.DEFAULT_ENABLED_FEATURES.stream()
-            .filter(e -> !e.equals(disabledDefault))
             .collect(ImmutableSet.toImmutableSet());
     List<String> expectedEnabled = new ArrayList<>();
     expectedEnabled.add("NewFeature");