[GTK] Enable indexed database for development builds
https://bugs.webkit.org/show_bug.cgi?id=107299

Patch by Martin Robinson <mrobinson@igalia.com> on 2013-01-18
Reviewed by Gustavo Noronha Silva.

Tools:

* Scripts/webkitperl/FeatureList.pm: Enable indexed database by default
for GTK+ development builds.

LayoutTests:

* platform/gtk/TestExpectations: Skip failing IDB tests and mark
flaky tests as flaky.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140187 268f45cc-cd09-0410-ab3c-d52691b4dbfc