Description

Before this patch, a fling of a scrollable will end up recommending deferred loading, but not a similarly large (or larger) jumpTo.

This adds an _impliedVelocity field to ScrollPosition that tracks how many pixels were forced in a single frame, and adds that to the activity's velocity when asking the ScrollPhysics whether we should defer.

Related Issues

Fixes #64124

Tests

I added the following tests:

Test that this works as expected when using jumpTo with large values.

Checklist

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• All existing and new tests are passing.
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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.