AllChangesIndexer: Make indexAll helper method private

This method being public dates back prior to Ifec986ef; at the time it
wasn't clear what all the entry points to ChangeBatchIndexer were going
to be. Now that we have a consistent interface for SiteIndexer, we don't
need this additional public method. Making it private means we can make
stronger assumptions about the input data, cleaning up code.

Change-Id: I3a2c08ea54be062f050317a5610d0df22e38f173

gerrit-server/src/main/java/com/google/gerrit/server/index/change/AllChangesIndexer.java

diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/index/change/AllChangesIndexer.java b/gerrit-server/src/main/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
index b989c01..183f9a1 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/index/change/AllChangesIndexer.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.index.change;
 
+import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.util.concurrent.Futures.successfulAsList;
 import static com.google.common.util.concurrent.Futures.transform;
 import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
@@ -43,7 +44,6 @@
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
@@ -136,17 +136,12 @@
     return indexAll(index, projects);
   }
 
-  public SiteIndexer.Result indexAll(ChangeIndex index, Iterable<ProjectHolder> projects) {
+  private SiteIndexer.Result indexAll(ChangeIndex index, SortedSet<ProjectHolder> projects) {
     Stopwatch sw = Stopwatch.createStarted();
     MultiProgressMonitor mpm = new MultiProgressMonitor(progressOut, "Reindexing changes");
-    Task projTask =
-        mpm.beginSubTask(
-            "projects",
-            (projects instanceof Collection)
-                ? ((Collection<?>) projects).size()
-                : MultiProgressMonitor.UNKNOWN);
-    Task doneTask =
-        mpm.beginSubTask(null, totalWork >= 0 ? totalWork : MultiProgressMonitor.UNKNOWN);
+    Task projTask = mpm.beginSubTask("projects", projects.size());
+    checkState(totalWork >= 0);
+    Task doneTask = mpm.beginSubTask(null, totalWork);
     Task failedTask = mpm.beginSubTask("failed", MultiProgressMonitor.UNKNOWN);
 
     List<ListenableFuture<?>> futures = new ArrayList<>();