Fix platform view transforms in CanvasKit

[harryterkelsen]

Description

Fixes transforms in CanvasKit by multiplying the transform matrices in the correct order.

Related Issues

Fixes flutter/flutter#61290

Tests

I added the following tests:

A test in embedded_views_test.dart which checks the transform matrix.

Checklist

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• I updated/added relevant documentation.
• All existing and new tests are passing.
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Reviewer Checklist

• I have submitted any presubmit flakes in this PR using the engine presubmit flakes form before re-triggering the failure.

Breaking Change

Did any tests fail when you ran them? Please read handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change.

[yjbanov]