Slight refactor

Author: tom-andersen

firebase-firestore/src/main/java/com/google/firebase/firestore/core/SQLiteComponentProvider.java

@@ -16,7 +16,6 @@
 
 import com.google.firebase.firestore.local.IndexBackfiller;
 import com.google.firebase.firestore.local.LocalSerializer;
-import com.google.firebase.firestore.local.LocalStore;
 import com.google.firebase.firestore.local.LruDelegate;
 import com.google.firebase.firestore.local.LruGarbageCollector;
 import com.google.firebase.firestore.local.Persistence;
@@ -36,12 +35,7 @@ protected Scheduler createGarbageCollectionScheduler(Configuration configuration
 
   @Override
   protected IndexBackfiller createIndexBackfiller(Configuration configuration) {
-    LocalStore localStore = getLocalStore();
-    return new IndexBackfiller(
-        getPersistence(),
-        configuration.getAsyncQueue(),
-        localStore::getIndexManagerForCurrentUser,
-        localStore::getLocalDocumentsForCurrentUser);
+    return new IndexBackfiller(getPersistence(), configuration.getAsyncQueue(), getLocalStore());
   }
 
   @Override

firebase-firestore/src/main/java/com/google/firebase/firestore/local/IndexBackfiller.java

@@ -44,6 +44,14 @@ public class IndexBackfiller {
   private final Supplier<LocalDocumentsView> localDocumentsViewOfCurrentUser;
   private int maxDocumentsToProcess = MAX_DOCUMENTS_TO_PROCESS;
 
+  public IndexBackfiller(Persistence persistence, AsyncQueue asyncQueue, LocalStore localStore) {
+    this(
+        persistence,
+        asyncQueue,
+        localStore::getIndexManagerForCurrentUser,
+        localStore::getLocalDocumentsForCurrentUser);
+  }
+
   public IndexBackfiller(
       Persistence persistence,
       AsyncQueue asyncQueue,

firebase-firestore/src/main/java/com/google/firebase/firestore/local/LocalDocumentsView.java

@@ -48,7 +48,7 @@
  * in remoteDocumentCache or local mutations for the document). The view is computed by applying the
  * mutations in the MutationQueue to the RemoteDocumentCache.
  */
-public class LocalDocumentsView {
+class LocalDocumentsView {
 
   private final RemoteDocumentCache remoteDocumentCache;
   private final MutationQueue mutationQueue;

firebase-firestore/src/test/java/com/google/firebase/firestore/local/LocalStoreTestCase.java

@@ -126,12 +126,7 @@ public void setUp() {
     queryEngine = new CountingQueryEngine(new QueryEngine());
     localStore = new LocalStore(localStorePersistence, queryEngine, User.UNAUTHENTICATED);
     localStore.start();
-    indexBackfiller =
-        new IndexBackfiller(
-            localStorePersistence,
-            new AsyncQueue(),
-            localStore::getIndexManagerForCurrentUser,
-            localStore::getLocalDocumentsForCurrentUser);
+    indexBackfiller = new IndexBackfiller(localStorePersistence, new AsyncQueue(), localStore);
   }
 
   @After