Remove last client of sql::DiagnosticErrorDelegate.

webkit/dom_storage/dom_storage_database.cc

Index: webkit/dom_storage/dom_storage_database.cc
diff --git a/webkit/dom_storage/dom_storage_database.cc b/webkit/dom_storage/dom_storage_database.cc
index 85f421838681e14904939201e9d75d59ec952408..4994d872ae0cce6f06499d67d4d16ff238ba8642 100644
--- a/webkit/dom_storage/dom_storage_database.cc
+++ b/webkit/dom_storage/dom_storage_database.cc
@@ -4,9 +4,9 @@
 
 #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"
@@ -15,13 +15,16 @@ 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
@@ -159,7 +162,8 @@ bool DomStorageDatabase::LazyOpen(bool create_if_needed) {
   }
 
   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.