Handle chrome:// links

[archon810]

Similar to #11824, can AMP handle chrome:// links without flagging them?

Here's where the validation is done:

amphtml/validator/validator-main.protoascii

Line 1926 in 680499c

value_url: {

.

These links aren't clickable in Chrome, but they're sometimes linkified by the sites to make right click url copying easier:

And they cause warnings:

Sample url with the issue: https://www.androidpolice.com/2019/07/17/15-tips-tricks-chrome-android-2019/.

[honeybadgerdontcare]

@ampproject/wg-security-privacy I don't see any issue with allowing the chrome:// protocol, does anyone else?

[molnarg]

No objection.