Replace ExceptionCode with DatabaseError in the openDatabase() code path.
https://bugs.webkit.org/show_bug.cgi?id=108724.

Reviewed by Alexey Proskuryakov.

Also made DatabaseBackend::performOpenAndVerify() a little more
straightforward and less repetitive.

No new tests.

* Modules/webdatabase/DOMWindowWebDatabase.cpp:
(WebCore::DOMWindowWebDatabase::openDatabase):
* Modules/webdatabase/Database.cpp:
(WebCore::Database::openAndVerifyVersion):
(WebCore::Database::performOpenAndVerify):
* Modules/webdatabase/Database.h:
(Database):
* Modules/webdatabase/DatabaseBackend.cpp:
(WebCore::DoneCreatingDatabaseOnExitCaller::DoneCreatingDatabaseOnExitCaller):
(WebCore::DoneCreatingDatabaseOnExitCaller::~DoneCreatingDatabaseOnExitCaller):
(DoneCreatingDatabaseOnExitCaller):
(WebCore::DoneCreatingDatabaseOnExitCaller::openSucceeded):
(WebCore::DatabaseBackend::performOpenAndVerify):
* Modules/webdatabase/DatabaseBackend.h:
* Modules/webdatabase/DatabaseManager.cpp:
(WebCore::DatabaseManager::openDatabase):
(WebCore::DatabaseManager::openDatabaseSync):
* Modules/webdatabase/DatabaseManager.h:
(DatabaseManager):
* Modules/webdatabase/DatabaseSync.cpp:
(WebCore::DatabaseSync::openAndVerifyVersion):
* Modules/webdatabase/DatabaseSync.h:
(DatabaseSync):
* Modules/webdatabase/DatabaseTask.cpp:
(WebCore::Database::DatabaseOpenTask::DatabaseOpenTask):
(WebCore::Database::DatabaseOpenTask::doPerformTask):
* Modules/webdatabase/DatabaseTask.h:
(WebCore::Database::DatabaseOpenTask::create):
(Database::DatabaseOpenTask):
* Modules/webdatabase/WorkerContextWebDatabase.cpp:
(WebCore::WorkerContextWebDatabase::openDatabase):
(WebCore::WorkerContextWebDatabase::openDatabaseSync):
* WebCore.gypi:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@141668 268f45cc-cd09-0410-ab3c-d52691b4dbfc