[MDCBottomSheet ]MDCBottomSheet didn't stop correctly at the bottom when it contains an UICollectionViewController with a MDCFlexibleHeaderViewController

[miworking3]

MDCBottomSheet didn't stop correctly at the bottom when it contains an UICollectionViewController with a MDCFlexibleHeaderViewController

Reproduction steps

1. git clone https://github.com/googlesamples/mlkit.git
2. go to mlkit/ios/showcase/vision-showcase/
3. run pod install --repo-update to install pods for the project and open the generated workspace and run it on a real device (Remember to select your provision profile and development team)
4. Select "Object Detection" on the start page (the first item)
5. Point it at an object, and it will pull up a MDCBottomSheet containing a [MLKResultListViewController](https://github.com/googlesamples/mlkit/blob/master/ios/showcase/vision-showcase/ShowcaseApp/Controllers/MLKResultListViewController.h) which is a nUICollectionViewController with MDCFlexibleHeaderViewController
6. Scroll down to the bottom of the list.

Expected behavior

It stops at the correct place with proper padding at the end of the bottom of the list.

Actual behavior

It stopped with bottom padding cut off.

Platform (please complete the following information)

• Device: iPhone 8+
• OS: iOS 13.3.1

Additional context

When the content of the list is less than a page, bottom padding was correct, it only happens to long list where it needs to scroll down to the end of the list.

[material-automation[bot]]

The title doesn't have a [Component] prefix.

[miworking3]

Hey material team,

Just want to check: do we have any plan to fix it in the coming season?

Thanks! Julie

[andrewoverton]

Hi @miworking3, Thank you for providing a gif. I don't actually understand what the bad behavior is by looking at the gif. It looks like typical scroll view bouncing. Can I only not see it because the cells have invisible borders?