Rewrite scoped_ptr<T>(NULL) to use the default ctor in sql/.

sql/connection.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 "sql/connection.h"
 
 #include <string.h>
 
 #include "base/files/file_path.h"
 #include "base/file_util.h"
@@ skipping 104 matching lines @@
 }
 
 Connection::Connection()
     : db_(NULL),
       page_size_(0),
       cache_size_(0),
       exclusive_locking_(false),
       transaction_nesting_(0),
       needs_rollback_(false),
       in_memory_(false),
-      poisoned_(false),
-      error_delegate_(NULL) {
-}
+      poisoned_(false) {}
 
 Connection::~Connection() {
   Close();
 }
 
 bool Connection::Open(const base::FilePath& path) {
   if (!histogram_tag_.empty()) {
     int64 size_64 = 0;
     if (file_util::GetFileSize(path, &size_64)) {
       size_t sample = static_cast<size_t>(size_64 / 1024);
@@ skipping 665 matching lines @@
   }
 
   // Best effort to put things back as they were before.
   const char kNoWritableSchema[] = "PRAGMA writable_schema = OFF";
   ignore_result(Execute(kNoWritableSchema));
 
   return ret;
 }
 
 }  // namespace sql