Revert of [Sync] Erase sync DB when corrupted

sync/syncable/on_disk_directory_backing_store.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 "sync/syncable/on_disk_directory_backing_store.h"
 
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "base/metrics/histogram.h"
 #include "sync/syncable/syncable-inl.h"
 
 namespace syncer {
 namespace syncable {
 
 namespace {
 
 enum HistogramResultEnum {
   FIRST_TRY_SUCCESS,
   SECOND_TRY_SUCCESS,
   SECOND_TRY_FAILURE,
   RESULT_COUNT
 };
 
 }  // namespace
 
 OnDiskDirectoryBackingStore::OnDiskDirectoryBackingStore(
     const std::string& dir_name,
     const base::FilePath& backing_file_path)
-    : DirectoryBackingStore(dir_name), backing_file_path_(backing_file_path) {
-  DCHECK(backing_file_path_.IsAbsolute());
+    : DirectoryBackingStore(dir_name),
+      allow_failure_for_test_(false),
+      backing_file_path_(backing_file_path) {
 }
 
 OnDiskDirectoryBackingStore::~OnDiskDirectoryBackingStore() {
 }
 
 DirOpenResult OnDiskDirectoryBackingStore::TryLoad(
     Directory::MetahandlesMap* handles_map,
     JournalIndex* delete_journals,
     MetahandleSet* metahandles_to_purge,
     Directory::KernelLoadInfo* kernel_load_info) {
@@ skipping 69 matching lines @@
   NOTREACHED() << "Crashing to preserve corrupt sync database";
 }
 
 const base::FilePath& OnDiskDirectoryBackingStore::backing_file_path() const {
   DCHECK(CalledOnValidThread());
   return backing_file_path_;
 }
 
 }  // namespace syncable
 }  // namespace syncer