Revert "Prevent usage of not initialized IndexCollection"

On master this change is causing an endless loop when running the
acceptance tests, see comments on I487111ad.

This reverts commit cf1bb5487e.

Change-Id: Ie81e9961b96e4206d55d9dc4c60514cd3704b4a7

gerrit-server/src/main/java/com/google/gerrit/server/index/IndexCollection.java

@@ -23,7 +23,6 @@ import com.google.inject.Singleton;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicReference;
 
 /** Dynamic pointers to the index versions used for searching and writing. */
@@ -31,29 +30,21 @@ import java.util.concurrent.atomic.AtomicReference;
 public class IndexCollection implements LifecycleListener {
   private final CopyOnWriteArrayList<ChangeIndex> writeIndexes;
   private final AtomicReference<ChangeIndex> searchIndex;
-  private final CountDownLatch initLatch;
 
   @Inject
   @VisibleForTesting
   public IndexCollection() {
     this.writeIndexes = Lists.newCopyOnWriteArrayList();
     this.searchIndex = new AtomicReference<>();
-    this.initLatch = new CountDownLatch(1);
   }
 
   /** @return the current search index version. */
   public ChangeIndex getSearchIndex() {
-    try {
-      initLatch.await();
-    } catch (InterruptedException e) {
-      // ignore
-    }
     return searchIndex.get();
   }
 
   public void setSearchIndex(ChangeIndex index) {
     ChangeIndex old = searchIndex.getAndSet(index);
-    initLatch.countDown();
     if (old != null && old != index && !writeIndexes.contains(old)) {
       old.close();
     }