Schedule them with timer when page loading is resumed. The tasks will be performed
in the original order. This fixes the problem that database callbacks could be missed
when page loading was deferred.
https://bugs.webkit.org/show_bug.cgi?id=49401

Patch by Yong Li <yoli@rim.com> on 2011-12-07
Reviewed by Darin Adler.

Manual test added: ManualTests/database-callback-deferred.html.

* dom/Document.cpp:
(WebCore::Document::Document):
(WebCore::Document::didReceiveTask):
(WebCore::Document::postTask):
(WebCore::Document::pendingTasksTimerFired):
(WebCore::Document::suspendScheduledTasks):
(WebCore::Document::resumeScheduledTasks):
* dom/Document.h:
* page/PageGroupLoadDeferrer.cpp:
(WebCore::PageGroupLoadDeferrer::PageGroupLoadDeferrer):
(WebCore::PageGroupLoadDeferrer::~PageGroupLoadDeferrer):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@102278 268f45cc-cd09-0410-ab3c-d52691b4dbfc