test(firestore): fix JSpecify compatibility issues on Java 8 (#13819)

Update Mockito mocks in Firestore tests to ignore annotations,
preventing ArrayStoreException when running tests on Java 8.
Specifically, mock StreamController, BidiStreamObserver, and
ClientStream classes with Mockito.withSettings().withoutAnnotations().
Refactor SilenceableBidiStreamTest to use programmatic mocks instead of
@mock annotations to allow configuring settings.

Author: lqiu96

java-firestore/google-cloud-firestore/src/test/java/com/google/cloud/firestore/ConformanceTest.java

@@ -85,7 +85,6 @@
 import org.junit.runners.AllTests;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Captor;
-import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 
@@ -616,13 +615,15 @@ private static final class ConformanceListenTestRunner
       extends BaseConformanceTestRunner<ListenTest> {
 
     @Captor private ArgumentCaptor<BidiStreamObserver<Message, Message>> streamObserverCapture;
-    @Mock private ClientStream<ListenRequest> noOpRequestObserver;
+    private final ClientStream<ListenRequest> noOpRequestObserver;
 
     private final Query watchQuery;
 
     private ConformanceListenTestRunner(
         String description, TestDefinition.ListenTest testParameters) {
       super(description, testParameters);
+      noOpRequestObserver =
+          Mockito.mock(ClientStream.class, Mockito.withSettings().withoutAnnotations());
       watchQuery = collection(ROOT_COLLECTION_PATH + "C").orderBy("a");
     }
 

java-firestore/google-cloud-firestore/src/test/java/com/google/cloud/firestore/LocalFirestoreHelper.java

@@ -20,6 +20,7 @@
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.withSettings;
 
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
@@ -415,7 +416,7 @@ public static <T> Answer<T> streamingResponse(
     return invocation -> {
       Object[] args = invocation.getArguments();
       ResponseObserver<T> observer = (ResponseObserver<T>) args[1];
-      observer.onStart(mock(StreamController.class));
+      observer.onStart(mock(StreamController.class, withSettings().withoutAnnotations()));
       for (T resp : response) {
         observer.onResponse(resp);
       }
@@ -432,7 +433,7 @@ public static <T> Answer<T> streamingResponseWithoutOnComplete(final T[] respons
     return invocation -> {
       Object[] args = invocation.getArguments();
       ResponseObserver<T> observer = (ResponseObserver<T>) args[1];
-      observer.onStart(mock(StreamController.class));
+      observer.onStart(mock(StreamController.class, withSettings().withoutAnnotations()));
       for (T resp : response) {
         observer.onResponse(resp);
       }

java-firestore/google-cloud-firestore/src/test/java/com/google/cloud/firestore/SilenceableBidiStreamTest.java

@@ -24,22 +24,22 @@
 import java.util.function.Consumer;
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
 
-@RunWith(MockitoJUnitRunner.class)
 public class SilenceableBidiStreamTest {
 
-  @Mock BidiStreamObserver<Integer, String> mockObserver;
+  BidiStreamObserver<Integer, String> mockObserver;
 
-  @Mock ClientStream<Integer> mockClientStream;
+  ClientStream<Integer> mockClientStream;
 
   SilenceableBidiStream<Integer, String> sut;
 
   @Before
   public void before() {
+    mockObserver =
+        Mockito.mock(BidiStreamObserver.class, Mockito.withSettings().withoutAnnotations());
+    mockClientStream =
+        Mockito.mock(ClientStream.class, Mockito.withSettings().withoutAnnotations());
     Consumer captureCall = Mockito.mock(Consumer.class);
     sut =
         new SilenceableBidiStream<>(
@@ -76,15 +76,17 @@ public void byDefault_theStreamWillPassThroughData_onResponse() {
 
   @Test
   public void byDefault_theStreamWillPassThroughData_onStart() {
-    StreamController controller = Mockito.mock(StreamController.class);
+    StreamController controller =
+        Mockito.mock(StreamController.class, Mockito.withSettings().withoutAnnotations());
     sut.onStart(controller);
     Mockito.verify(mockObserver, Mockito.times(1)).onStart(controller);
     Mockito.verifyNoMoreInteractions(mockClientStream, mockObserver, controller);
   }
 
   @Test
   public void byDefault_theStreamWillPassThroughData_onReady() {
-    ClientStream<Integer> client = Mockito.mock(ClientStream.class);
+    ClientStream<Integer> client =
+        Mockito.mock(ClientStream.class, Mockito.withSettings().withoutAnnotations());
     sut.onReady(client);
     Mockito.verify(mockObserver, Mockito.times(1)).onReady(client);
     Mockito.verifyNoMoreInteractions(mockClientStream, mockObserver, client);