* ScrolledPositionedList: Fix padding for horizontal lists.

PiperOrigin-RevId: 280499058

* ScrollablePositionedList: Add separator builder to PositionedList.

PiperOrigin-RevId: 281290556

* ScrollablePositionedList: add separated constructor to ScrollablePositionedList.

Fixes: https://github.com/google/flutter.widgets/issues/34
PiperOrigin-RevId: 281290603

* Rename setUp to setUpWidgetTest to avoid confusion with dart's setUp method.

PiperOrigin-RevId: 281290904

* Clean up violations of Dart lint "prefer_void_to_null".

Use `void` instead of `Null` wherever possible.

More information: http://go/dart-trivial-lint-cleanup-lsc

Tested:
    TAP --sample ran all affected tests and none failed
    http://test/OCL:282596855:BASE:282596843:1574805350425:a8e25c04
PiperOrigin-RevId: 282721649

* Clean up violations of Dart lint "omit_local_variable_types".

Remove local variable type annotations when they can be exactly inferred.

More information: http://go/dart-trivial-lint-cleanup-lsc

Tested:
    TAP --sample ran all affected tests and none failed
    http://test/OCL:282916385:BASE:282903988:1574940403648:b0a29791
PiperOrigin-RevId: 282921638

* Update flutter.widgets CHANGELOG with ScrollablePositionList bug fixes for next release.

PiperOrigin-RevId: 284032643

* Make padding test names more uniform.

PiperOrigin-RevId: 284901918

* Fix padding for reversed lists.

PiperOrigin-RevId: 284904351

* Clean up violations of Dart lint "omit_local_variable_types".

Remove local variable type annotations when they can be exactly inferred.

More information: http://go/dart-trivial-lint-cleanup-lsc

Tested:
    TAP --sample ran all affected tests and none failed
    http://test/OCL:285936540:BASE:285918090:1576575736279:8ae637bc
PiperOrigin-RevId: 285940032

*  Exclude semantic for scrollable positioned list.

PiperOrigin-RevId: 286092487

*  Add offset getter for LinkedScrollControllerGroup.

PiperOrigin-RevId: 286483185

* Fix some deprecation warnings

Make the following replacements to avoid deprecation warnings from
flutter 1.12.1:

ancestorStateOfType(T) => findAncestorStateOfType<T>()
inheritFromWidgetOfExactType(T) => dependOnInheritedWidgetOfExactType<T>()

PiperOrigin-RevId: 286654847

* ScollablePositionedList: Add key parameter to ScrollablePositionedList.

PiperOrigin-RevId: 286655774

* Add a GitHub pull request template

Add a GitHub pull request template for flutter_widgets, mostly based
on Flutter's PR template.  This is primarily to remind myself to run
`flutter analyze` and `flutter test` before publishing a pull
request.

Also fix a typo in CHANGELOG.md.

PiperOrigin-RevId: 287035590

*  Add isAttached to ItemScrollerController, it checks if the ItemScrollerController is attached to the ScrollablePositionedList, should be similar to ScrollController.hasClient.

PiperOrigin-RevId: 287142661

*  Throw on LinkedScrollControllerGroup.offset when no controllers are attached.

PiperOrigin-RevId: 287343483

* Update to CHANGELOG for ScrollablePositionedList.

PiperOrigin-RevId: 287344711

Co-authored-by: a-googler <github-admin+a-googler@google.com>
Co-authored-by: David Morgan <davidmorgan@google.com>
Co-authored-by: Kenzie Schmoll <43759233+kenzieschmoll@users.noreply.github.com>
Co-authored-by: James D. Lin <jamesderlin@users.noreply.github.com>