Enable class initializer policy for synthetics

Change-Id: Id130c8d9396ec03c3505b20808c63f85559cc2b1
diff --git a/src/main/java/com/android/tools/r8/horizontalclassmerging/PolicyScheduler.java b/src/main/java/com/android/tools/r8/horizontalclassmerging/PolicyScheduler.java
index 1a5e5a7..01a85ee 100644
--- a/src/main/java/com/android/tools/r8/horizontalclassmerging/PolicyScheduler.java
+++ b/src/main/java/com/android/tools/r8/horizontalclassmerging/PolicyScheduler.java
@@ -100,7 +100,10 @@
   private static void addRequiredSingleClassPolicies(
       AppView<? extends AppInfoWithClassHierarchy> appView,
       ImmutableList.Builder<SingleClassPolicy> builder) {
-    builder.add(new CheckSyntheticClasses(appView), new NoKeepRules(appView));
+    builder.add(
+        new CheckSyntheticClasses(appView),
+        new NoKeepRules(appView),
+        new NoClassInitializerWithObservableSideEffects());
   }
 
   private static void addSingleClassPoliciesForMergingNonSyntheticClasses(
@@ -111,7 +114,6 @@
     builder.add(
         new NotMatchedByNoHorizontalClassMerging(appView),
         new NoAnnotationClasses(),
-        new NoClassInitializerWithObservableSideEffects(),
         new NoDirectRuntimeTypeChecks(appView, mode, runtimeTypeCheckInfo),
         new NoEnums(appView),
         new NoInterfaces(appView, mode),
@@ -129,7 +131,6 @@
     List<SingleClassPolicy> policies =
         ImmutableList.of(
             new NoAnnotationClasses(),
-            new NoClassInitializerWithObservableSideEffects(),
             new NoDirectRuntimeTypeChecks(appView, mode),
             new NoEnums(appView),
             new NoInterfaces(appView, mode),