Add amp-bind optimizer

[jridgewell]

See ampproject/amphtml#32851

Part of ampproject/amphtml#27590

[sebastianbenz]

Nice!

Two comments:

• using data-amphtml-binding instead of I-amphtml-binding would mean that we wouldn't have to update the validator
• can you please add a test here: https://github.com/ampproject/amp-toolbox/tree/main/packages/optimizer/spec/transformers/valid. You can run npm run optimier:test:snapshot to generate the expected output files

[sebastianbenz]

We should enable this by default.

Suggested change

	this.enabled_ = !!config.optimizeAmpBind;
	this.enabled_ = config.optimizeAmpBind !== false;

[sebastianbenz]

Or did you intentionally leave this disabled until the validator changes are live?

[jridgewell]

Yup, this is intentionally disabled until validator changes are live in AMP Cache. I was gonna follow up with a PR to enable it afterwards.

[sebastianbenz]

//cc @westonruter @schlessera for porting this to the PHP optimizer.

[jridgewell]

• using data-amphtml-binding instead of I-amphtml-binding would mean that we wouldn't have to update the validator

I actually chose not to do this, since the attribute can only be valid in transformed outputs. Data attributes are always valid.

• can you please add a test here: https://github.com/ampproject/amp-toolbox/tree/main/packages/optimizer/spec/transformers/valid. You can run npm run optimier:test:snapshot to generate the expected output files

Working on that now.

[jridgewell]

Yup, this is intentionally disabled until validator changes are live in AMP Cache. I was gonna follow up with a PR to enable it afterwards.

[jridgewell]

Tests added

[sebastianbenz]

Thanks!