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cherry-pick of #165008

## Impacted Users

Impeller users.

## Impact Description

Text that is rotated 180 degrees exactly will render as if it is scaled by {-1, 1} instead of {-1, -1}.

## Workaround

You can rotate text 180.001 degrees instead but the fidelity will be less.

## Risk

If it's wrong it could break all text rendering.  There are golden tests for it.

## Test Coverage

Golden tests (which are not run on release branches)

## Validation Steps

#164958 has reproduction code

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cherry-pick of flutter#165008

Impeller users.

Text that is rotated 180 degrees exactly will render as if it is scaled by {-1, 1} instead of {-1, -1}.

You can rotate text 180.001 degrees instead but the fidelity will be less.

If it's wrong it could break all text rendering.  There are golden tests for it.

Golden tests (which are not run on release branches)

flutter#164958 has reproduction code

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)

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fixes flutter#164958

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md
[Features we expect every widget to implement]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes
[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md