Turn experiments.js into a service

[lannka]

2 reasons:

1. experiments.js right now is a shared code between extensions. Each extension toggles experiments independently to each other, and the results are not shared, which can be an issue that different extension will have different experiment on/off status.
2. experiments.js is now 300+ lines of code. Due to its popularity, it's compiled into almost half of the extensions, which is a waste of bandwidth.

@dvoytenko @erwinmombay thoughts?

[dvoytenko]

I think we can make it a service. Duplication over extensions is definitely problematic especially b/c the set of toggles can diverge. One possible nuance that we may need to work around - the same library is used also experiments.html, which is not otherwise governed by an AMP Runtime. So, that might cause some compilation issues.

[ampprojectbot]

This issue hasn't been updated in awhile. @dvoytenko Do you have any updates?

[ampprojectbot]

This issue hasn't been updated in awhile. @dvoytenko Do you have any updates?

[ampprojectbot]

This issue hasn't been updated in awhile. @dvoytenko Do you have any updates?

[lannka]

in the spirit of moving shared code to service, @jridgewell would you like to take this ?

[ampprojectbot]

This issue hasn't been updated in awhile. @jridgewell Do you have any updates?

[lannka]

@kristoferbaxter what do you think about prioritizing this in the upcoming fixit summit? It's going to save quite a lot bytes in each extension.

[kristoferbaxter]

I'll add it to the performance wg list for fixit and see if we can do it.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. Thank you for your contributions.