GitLab

Ensure callback objects held by the Indexed DB dispatcher are released
before WebKit and V8 are torn down, since the callback objects hold V8
handles.

This is the same patch as crrev.com/50333004 which landed as r232620
but reverted as r232649 due to timeouts on XP - I just tweaked the
test constants slightly.

BUG=308988
TBR=marja@chromium.org,jamesr@chromium.org,dgrogan@chromium.org

Review URL: https://codereview.chromium.org/58113002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233505 0039d316-1c4b-4281-b951-d872f2087c98