https://bugs.webkit.org/show_bug.cgi?id=27836

WebCore: 

Reviewed by David Kilzer.

Tests: storage/change-version-handle-reuse.html
       storage/change-version.html

* bindings/v8/custom/V8DatabaseCustom.cpp:
(WebCore::CALLBACK_FUNC_DECL): Implement the V8 binding for database.changeVersion().
(WebCore::createTransaction): Fix a bug that was checking the wrong argument index to save the success callback.
* storage/Database.cpp:
(WebCore::updateGuidVersionMap): Safely update the Guid/version hash map.
(WebCore::Database::~Database): Remove code that removes the database from the guid->database and guid->version maps.
(WebCore::Database::setVersionInDatabase): Add a comment to explain some behaviour.
(WebCore::Database::close): Move the code that updates the maps from the destructor to here.
(WebCore::Database::performOpenAndVerify): Call updateGuidVersionMap instead of setting the hash map directly.
(WebCore::Database::setExpectedVersion): Update the in memory guid->version map when we want to update the database version.

LayoutTests: 

Reviewed by  David Kilzer.

* storage/change-version-expected.txt: Added.
* storage/change-version-handle-reuse-expected.txt: Added.
* storage/change-version-handle-reuse.html: Added.
* storage/change-version.html: Added.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@49018 268f45cc-cd09-0410-ab3c-d52691b4dbfc