SPC on Chrome Android available for developer testing

Hi folks,

I'm excited to announce that as of Chrome Canary version 107.0.5258.0, it
is now (once more) possible to test SPC on Chrome Android locally on your
device.

To try it out, install Chrome Canary on your Android device, and visit
chrome://flags#enable-secure-payment-confirmation-android . Set the flag to
'Enabled' and choose to re-launch. After this, you can visit
https://rsolomakhin.github.io/ or https://spc-shop-demo.glitch.me/ and try
out our demos - or build your own!

Important caveats:

   1. Android does not support discoverable credentials at this time. As
   such, you have to use 'residentKey: preferred' (rather than required) in
   your credential creation code (example
   <https://github.com/rsolomakhin/rsolomakhin.github.io/blob/master/pr/spc/pr.js#L193>
   ).
      - Setting 'preferred' for an SPC credential will only work for Chrome
      versions M106 and above and *will throw* in older versions - so if
      you are editing any of your own pilots/demos please make sure to
      version-detect it.
   2. At this time, SPC on Chrome Android is still using the user profile
   database for credential storage, identical to desktop Chrome. However we do
   not intend to launch this way - we are building support for SPC into the
   Android credential store APIs and will switch to using that in the future
   (before launch).
   3. We do not yet support the (also experimental) opt-out feature on SPC
   for Chrome Android. Working on it!
   4. This functionality is very experimental. It may break or have adverse
   effects on your device that we haven't considered yet. *Use at your own
   risk*, and do not expect any credentials created for it to work in
   future releases.

Feedback welcome, as always. Note that we do not have a target
date/milestone for a Chrome Android launch at this time, as it will depend
significantly on the underlying credential store work.

Thanks,
Stephen

-- 
smcgruer • he / him