Provide remote.html type ad request enhancement for amp-ad when using fast fetch

[jasti]

In slow fetch 3P amp-ad request scenario, publishers used the remote.html approach to enhance ad requests with cookie information. Since fast fetch is all XHR based, this approach will not work. This feature is to allow publishers to decorate an ad request typically for operations like reading their own cookies from another domain or the same domain and update the ad request before sending to the ad server.
CC @lannka

[dknecht]

Would non-fast fetch amp-ads still use remote.html?

[keithwrightbos]

For Adsense and Doubleclick, ideally no otherwise a publisher would need to potentially maintain both remote.html and new the implementation in order to ensure parity.

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On Sat, Feb 25, 2017 at 1:29 PM Dane ***@***.***> wrote: Would non-fast fetch amp-ads still use remote.html? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#7772 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABr0L_SLTPL3-Wl60k58SMVPPDy8zvMSks5rgHLvgaJpZM4MKmj1> .

[jasti]

Assigning to @tdrl & @keithwrightbos since they are leading the design.

[keithwrightbos]

See i2i: #8551