Description

Currently showModalBottomSheet always removes the top padding from the MediaQuery since it would be 'consumed' since the bottomsheet wont span the entire height of the window.
This is however only correct if the sheet is not scroll controlled, because if it is scroll controlled then the bottomsheet will get a maximum size of the whole window again.
So this PR makes showModalBottomSheet actually consume the padding if the bottomsheet is scrollcontrolled.

Related Issues

Fixes #39205

Tests

I added the following tests:

• Updated the name of the old test to indicate that it should only happen if not scroll controlled
• Added a new test that checks that the bottomsheet is inset by the top padding

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I signed the CLA.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
• The analyzer (flutter analyze --flutter-repo) does not report any problems on my PR.
• I am willing to follow-up on review comments in a timely manner.

Breaking Change

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

Not sure if this is considered a breaking, I don't think any tests will fail but anyone that is using a workaround like proposed in #39205 will get a double padding by this fix

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change. If not, delete the remainder of this section.
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