Add an IO thread index bitmap to disk cache.

net/disk_cache/backend_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/basictypes.h"
 #include "base/file_util.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
 #include "base/threading/platform_thread.h"
@@ skipping 2235 matching lines @@
 TEST_F(DiskCacheTest, Backend_UsageStats) {
   MessageLoopHelper helper;
 
   ASSERT_TRUE(CleanupCacheDir());
   scoped_ptr<disk_cache::BackendImpl> cache;
   cache.reset(new disk_cache::BackendImpl(
                   cache_path_, base::MessageLoopProxy::current(),
                   NULL));
   ASSERT_TRUE(NULL != cache.get());
   cache->SetUnitTestMode();
-  ASSERT_EQ(net::OK, cache->SyncInit());
+  ASSERT_EQ(net::OK, cache->SyncInit(NULL));
 
   // Wait for a callback that never comes... about 2 secs :). The message loop
   // has to run to allow invocation of the usage timer.
   helper.WaitUntilCacheIoFinished(1);
 }
 
 void DiskCacheBackendTest::BackendDoomAll() {
   InitCache();
 
   disk_cache::Entry *entry1, *entry2;
@@ skipping 301 matching lines @@
   // Ping the oldest entry.
   cache_->OnExternalCacheHit("key0");
 
   TrimForTest(false);
 
   // Make sure the older key remains.
   EXPECT_EQ(1, cache_->GetEntryCount());
   ASSERT_EQ(net::OK, OpenEntry("key0", &entry));
   entry->Close();
 }