Remove last client of sql::DiagnosticErrorDelegate.

webkit/dom_storage/dom_storage_database.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 "webkit/dom_storage/dom_storage_database.h"
 
+#include "base/bind.h"
 #include "base/file_util.h"
 #include "base/logging.h"
-#include "sql/diagnostic_error_delegate.h"
 #include "sql/statement.h"
 #include "sql/transaction.h"
 #include "third_party/sqlite/sqlite3.h"
 
 namespace {
 
 const base::FilePath::CharType kJournal[] = FILE_PATH_LITERAL("-journal");
 
-class HistogramUniquifier {
- public:
-  static const char* name() { return "Sqlite.DomStorageDatabase.Error"; }
-};
-
-sql::ErrorDelegate* GetErrorHandlerForDomStorageDatabase() {
-  return new sql::DiagnosticErrorDelegate<HistogramUniquifier>();
+void DatabaseErrorCallback(int error, sql::Statement* stmt) {
+  // Without a callback to ignore errors,
+  // DomStorageDatabaseTest.TestCanOpenFileThatIsNotADatabase fails with:
+  // ERROR:connection.cc(735)] sqlite error 522, errno 0: disk I/O error
+  // FATAL:connection.cc(750)] disk I/O error
+  // <backtrace>
+  // <crash>
+  //
+  // TODO(shess): If/when infrastructure lands which can allow tests
+  // to handle SQLite errors appropriately, remove this.
 }
 
 }  // anon namespace
 
 namespace dom_storage {
 
 // static
 base::FilePath DomStorageDatabase::GetJournalFilePath(
     const base::FilePath& database_path) {
   base::FilePath::StringType journal_file_name =
@@ skipping 117 matching lines @@
 
   if (!database_exists && !create_if_needed) {
     // If the file doesn't exist already and we haven't been asked to create
     // a file on disk, then we don't bother opening the database. This means
     // we wait until we absolutely need to put something onto disk before we
     // do so.
     return false;
   }
 
   db_.reset(new sql::Connection());
-  db_->set_error_delegate(GetErrorHandlerForDomStorageDatabase());
+  db_->set_histogram_tag("DomStorageDatabase");

[marja, 2013/05/23 05:32:29]

Will we get the same error histogram information via this than what we used to
get with the GetErrorHandlerForDomStorageDatabase? (I don't know what it does,
but looks like it gathers some histograms about... error counts??)

[Scott Hess - ex-Googler, 2013/05/23 05:45:37]

Old School: Complicated function template calling class template, blah blah
blah.  Very cargo-cult.

New School: Tell sql::Connection a tag to identify you, it takes care of things.

Recently I have changed the histograms from Sqlite.<tag>.Error to
Sqlite.Error.<tag>, but in return they include extended error codes, and it's
now also tracking Sqlite.Version.<tag> (if you use MetaTable versioning) and
Sqlite.SizeKB.<tag> (size at startup), and I'm hopeful other ideas for
across-the-board additions will come to mind.

+  db_->set_error_callback(base::Bind(&DatabaseErrorCallback));
 
   if (file_path_.empty()) {
     // This code path should only be triggered by unit tests.
     if (!db_->OpenInMemory()) {
       NOTREACHED() << "Unable to open DOM storage database in memory.";
       failed_to_open_ = true;
       return false;
     }
   } else {
     if (!db_->Open(file_path_)) {
@@ skipping 122 matching lines @@
       CreateTableV2() &&
       CommitChanges(false, values) &&
       migration.Commit();
 }
 
 void DomStorageDatabase::Close() {
   db_.reset(NULL);
 }
 
 }  // namespace dom_storage