Fix up ordering in ProfileIOData.

Fix up ordering in ProfileIOData.

It's important to destroy the ResourceContext before we start destroying the URLRequestContext and the members it owns, because destroying the ResourceContext will cancel the pending URLRequests for that ResourceContext in the ResourceDispatcherHost. Those URLRequests may reference the URLRequestContexts in their destructors, so we need to make sure ResourceContext is destroyed first.

While doing this, I did some other cleanup:
  * discovered that we could eliminate HostContentSettingsMap from ProfileIOData, w00t!
  * reordered URLRequestContext after the members it points to, so it gets destroyed before they get destroyed
  * moved the virtuals in ProfileIOData::ResourceContext to be public, since the parent class changed them to be public

BUG=90971
TEST=none


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=133793

[willchan no longer on Chromium, 2012-04-24 21:02:55]

+eroman

[Elliot Glaysher, 2012-04-24 21:06:33]

lgtm

[commit-bot: I haz the power, 2012-04-24 21:09:43]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/willchan@chromium.org/10174008/5001

[commit-bot: I haz the power, 2012-04-24 22:55:21]

Change committed as 133793