Fixed backface visibility.

[sainthkh]

• Closes backface-visibility: hidden doesn't hide elements from cypress #2985

User facing changelog

When backface-visibility: hidden and rotateX(180deg), to.be.hidden is now true.

Additional details

• Why was this change necessary?

Like card example provided, sometimes we want something to be invisible when it is rotateX(180deg) or rotateY(180deg).

Now, we can check them out.

• What is affected by this change?

I just added some tests and related code.

• Any implementation details to explain?

It uses simplified version of backface culling.

How has the user experience changed?

Now we can check backface.

PR Tasks

• Have tests been added/updated?
• Has a PR for user-facing changes been opened in cypress-documentation?
• Have API changes been updated in the type definitions?
• Have new configuration options been added to the cypress.schema.json?

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PR Review Checklist

If any of the following requirements can't be met, leave a comment in the review selecting 'Request changes', otherwise 'Approve'.

User Experience

• The feature/bugfix is self-documenting from within the product.
• The change provides the end user with a way to fix their problem (no dead ends).

Functionality

• The code works and performs its intended function with the correct logic.
• Performance has been factored in (for example, the code cleans up after itself to not cause memory leaks).
• The code guards against edge cases and invalid input and has tests to cover it.

Maintainability

• The code is readable (too many nested 'if's are a bad sign).
• Names used for variables, methods, etc, clearly describe their function.
• The code is easy to understood and there are relevant comments explaining.
• New algorithms are documented in the code with link(s) to external docs (flowcharts, w3c, chrome, firefox).
• There are comments containing link(s) to the addressed issue (in tests and code).

Quality

• The change does not reimplement code.
• There's not a module from the ecosystem that should be used instead.
• There is no redundant or duplicate code.
• There are no irrelevant comments left in the code.
• Tests are testing the code’s intended functionality in the best way possible.

Internal

• The original issue has been tagged with a release in ZenHub.

[sainthkh]

I guess big cookie test failed because of timeout.

But interestingly, it doesn't work on my local ubuntu with develop branch code.

[kuceb]

@sainthkh what happens if the element has rotateY(180deg) and its parent has rotateY(-180deg)? I believe the transform property will say 180 degrees when in reality the element would be visible.

[sainthkh]

@bkucera I'll check it out.

[sainthkh]

@bkucera Interestingly, that didn't happen.

I created this code pen and tested with Chrome 78 and Firefox 70 on Ubuntu 18.04. I couldn't see "hello transformed world".

p.s. server-integration-tests failed because of timeout.

[kuceb]

thanks @sainthkh , I'll rerun CI

[sainthkh]

@chrisbreiding Fixed.