Auto merge of #18966 - chenpighead:Bug1399049-transform-animate-refactoring, r=hiikezoe

stylo: Avoid using InterpolateMatrix as a fallback for matched transform function pair

In the current implementation, if there is any interpolation error in a matched
transform function pair, we fall-back to use InterpolateMatrix unconditionally.
However, the error could be caused by:

1. mismatched transform function pair
2. matched transform function pair within at least one undecomposable matrix.

Using InterpolateMatrix for case 1 makes sense, however, using InterpolateMatrix
for case 2 does not. According to the spec, we should just report error for
case 2, and let the caller do the fallback procedure. Using InterpolateMatrix
for case 2 will go through more unnecessary code path, and produce more memory
usage and calculation cost, which should be avoidable.

In this patch, we add an extra pass to check if a transform function pair have
matched operations in advance. With this information, we can easily tell whether
the interpolation error in a equal-length transform function pair is caused by
case 1 or case 2. So, we can avoid the unnecessary cost.

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<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [Bug 1399049](https://bugzilla.mozilla.org/show_bug.cgi?id=1399049)
- [X] These changes do not require tests because the change is for some performance gain, and we have tests to ensure that we won't regress the existing behavior already.

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