I recently fixed issue 651993, which was related to some network objects owned by the ProfileImplIOData being deleted URLRequests owned by the ProfileIOData.  While the immediate crash issue is fixed, there's still a lot of ugliness about who owns what here.  We should fix similar cases of this, and stick most network things ProfileIOData itself owns into its own URLRequestContextStorage object, to ensure a reasonable destruction order.

Long term, we may want to use URLRequestContextBuilder to create anything, but that's beyond the intended scope of this bug.