Investigate how to make consent information available to Google #89

Sam to review Google specs and consider:

• How can we dynamically inform Google whether personalised ads can serve. If Google as a vendor on the GVL has consent? The only way to communicate dynamic consent to DFP is through a call to googletag.pubads().setRequestNonPersonalizedAds() (boolean). See https://support.google.com/dfp_premium/answer/7678538
• How should we communicate to Google which vendors have consent: They are using non-standard OpenRTB conveyance of consent info at User.ext.consented_provider_settings - see full spec.