xds, api: minor cleanup to address linter suggestions (#9116)

Author: sergiitk

api/src/test/java/io/grpc/ManagedChannelRegistryTest.java

@@ -253,11 +253,6 @@ public NewChannelBuilderResult newChannelBuilder(
         throw new AssertionError();
       }
     });
-    class MockChannelBuilder extends ForwardingChannelBuilder<MockChannelBuilder> {
-      @Override public ManagedChannelBuilder<?> delegate() {
-        throw new UnsupportedOperationException();
-      }
-    }
 
     registry.register(new BaseProvider(true, 4) {
       @Override

xds/src/test/java/io/grpc/xds/CdsLoadBalancer2Test.java

@@ -586,7 +586,7 @@ private final class FakeLoadBalancerProvider extends LoadBalancerProvider {
 
     @Override
     public LoadBalancer newLoadBalancer(Helper helper) {
-      FakeLoadBalancer balancer = new FakeLoadBalancer(policyName, helper);
+      FakeLoadBalancer balancer = new FakeLoadBalancer(policyName);
       childBalancers.add(balancer);
       return balancer;
     }
@@ -618,14 +618,12 @@ public NameResolver.ConfigOrError parseLoadBalancingPolicyConfig(
 
   private final class FakeLoadBalancer extends LoadBalancer {
     private final String name;
-    private final Helper helper;
     private Object config;
     private Status upstreamError;
     private boolean shutdown;
 
-    FakeLoadBalancer(String name, Helper helper) {
+    FakeLoadBalancer(String name) {
       this.name = name;
-      this.helper = helper;
     }
 
     @Override
@@ -643,16 +641,6 @@ public void shutdown() {
       shutdown = true;
       childBalancers.remove(this);
     }
-
-    void deliverSubchannelState(final Subchannel subchannel, ConnectivityState state) {
-      SubchannelPicker picker = new SubchannelPicker() {
-        @Override
-        public PickResult pickSubchannel(PickSubchannelArgs args) {
-          return PickResult.withSubchannel(subchannel);
-        }
-      };
-      helper.updateBalancingState(state, picker);
-    }
   }
 
   private static final class FakeXdsClient extends XdsClient {

xds/src/test/java/io/grpc/xds/LegacyLoadBalancerConfigFactoryTest.java

@@ -53,10 +53,13 @@ public void roundRobin() throws ResourceInvalidException {
 
   @Test
   public void ringHash() throws ResourceInvalidException {
-    Cluster cluster = Cluster.newBuilder().setLbPolicy(LbPolicy.RING_HASH).setRingHashLbConfig(
-        RingHashLbConfig.newBuilder()
-            .setMinimumRingSize(UInt64Value.newBuilder().setValue(1).build())
-            .setMaximumRingSize(UInt64Value.newBuilder().setValue(2).build()).build()).build();
+    Cluster cluster = Cluster.newBuilder()
+        .setLbPolicy(LbPolicy.RING_HASH)
+        .setRingHashLbConfig(
+            RingHashLbConfig.newBuilder()
+                .setMinimumRingSize(UInt64Value.of(1))
+                .setMaximumRingSize(UInt64Value.of(2)))
+        .build();
 
     LbConfig lbConfig = ServiceConfigUtil.unwrapLoadBalancingConfig(
         LegacyLoadBalancerConfigFactory.newConfig(cluster, true));
@@ -85,9 +88,11 @@ public void ringHash_invalidHash() throws ResourceInvalidException {
   public void leastRequest() throws ResourceInvalidException {
     System.setProperty("io.grpc.xds.experimentalEnableLeastRequest", "true");
 
-    Cluster cluster = Cluster.newBuilder().setLbPolicy(LbPolicy.LEAST_REQUEST)
-        .setLeastRequestLbConfig(LeastRequestLbConfig.newBuilder()
-            .setChoiceCount(UInt32Value.newBuilder().setValue(10).build())).build();
+    Cluster cluster = Cluster.newBuilder()
+        .setLbPolicy(LbPolicy.LEAST_REQUEST)
+        .setLeastRequestLbConfig(
+            LeastRequestLbConfig.newBuilder().setChoiceCount(UInt32Value.of(10)))
+        .build();
 
     LbConfig lbConfig = ServiceConfigUtil.unwrapLoadBalancingConfig(
         LegacyLoadBalancerConfigFactory.newConfig(cluster, true));