Global Styles: Alternative means of variation cloning

[tyxla]

Proposed Changes

Introduces an alternative cloning mechanism in case structuredClone doesn't exist. Adding since this seems to be occurring for hundreds of users per day.

Why are these changes being made?

Resolves https://a8c.sentry.io/issues/6191478529/?project=6313676&referrer=project-issue-stream

Testing Instructions

See #97808

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug fix/gutenberg-bridge-clone-variation on your sandbox.

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129719

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129719&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129719&env=a8c-for-agencies

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~25 bytes added 📈 [gzipped])

name      parsed_size           gzip_size
patterns        +57 B  (+0.0%)      +25 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~23 bytes added 📈 [gzipped])

name                                                                         parsed_size           gzip_size
async-load-automattic-global-styles-src-components-global-styles-variations        +57 B  (+0.0%)      +23 B  (+0.0%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.