Do not validity check safe-browsing store if not opened.

chrome/browser/safe_browsing/safe_browsing_store_file.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 "chrome/browser/safe_browsing/safe_browsing_store_file.h"
 
 #include "base/md5.h"
 #include "base/metrics/histogram.h"
 
 namespace {
@@ skipping 226 matching lines @@
   // also removed.
   const FilePath journal_filename(
       filename_.value() + FILE_PATH_LITERAL("-journal"));
   if (file_util::PathExists(journal_filename))
     file_util::Delete(journal_filename, false);
 
   return true;
 }
 
 bool SafeBrowsingStoreFile::CheckValidity() {
-  if (empty_)
+  // The file was either empty or never opened.  The empty case is
+  // presumed not to be invalid.  The never-opened case can happen if
+  // BeginUpdate() fails for any databases, and should already have
+  // caused the corruption callback to fire.
+  if (!file_.get())
     return true;
 
-  // If the file was not empty, it should be open.
-  DCHECK(file_.get());
-
   if (!FileRewind(file_.get()))
     return OnCorruptDatabase();
 
   int64 size = 0;
   if (!file_util::GetFileSize(filename_, &size))
     return OnCorruptDatabase();
 
   base::MD5Context context;
   base::MD5Init(&context);
 
@@ skipping 486 matching lines @@
   out->insert(out->end(), sub_chunks_cache_.begin(), sub_chunks_cache_.end());
 }
 
 void SafeBrowsingStoreFile::DeleteAddChunk(int32 chunk_id) {
   add_del_cache_.insert(chunk_id);
 }
 
 void SafeBrowsingStoreFile::DeleteSubChunk(int32 chunk_id) {
   sub_del_cache_.insert(chunk_id);
 }