Update functions to be consistent with other code.

[robert-ancell]

Helper functions first, then callbacks/implementations, then public functions.
Add function comments.
Use consistent function naming.
Remove unnecessary protoypes.
Make a function static that wasn't.

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  writing and running engine tests.
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It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat.

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat.

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

Reviewers: Read the Tree Hygiene page and make sure this patch meets those guidelines before LGTMing.

[cbracken]

Thanks!

[fluttergithubbot]

This pull request is not suitable for automatic merging in its current state.

• The status or check suite build_and_test_linux_unopt_debug has failed. Please fix the issues identified (or deflake) before re-applying this label.