Cover more test/widgets tests with leak tracking #6

[ksokolovskyi]

Description

This PR changes testWidgets by testWidgetsWithLeakTracking in number of flutter/test/widgets tests according to the dart-lang/leak_tracker#134.

Tests

• Updates notification_test.dart to use testWidgetsWithLeakTracking;
• Updates obscured_animated_image_test.dart to use testWidgetsWithLeakTracking;
• Updates opacity_repaint_test.dart to use testWidgetsWithLeakTracking;
• Updates opacity_test.dart to use testWidgetsWithLeakTracking;
• Updates overflow_bar_test.dart to use testWidgetsWithLeakTracking;
• Updates overflow_box_test.dart to use testWidgetsWithLeakTracking;
• Updates overlay_portal_test.dart to use testWidgetsWithLeakTracking;
• Updates overscroll_indicator_test.dart to use testWidgetsWithLeakTracking;
• Updates overscroll_stretch_indicator_test.dart to use testWidgetsWithLeakTracking;
• Updates page_forward_transitions_test.dart to use testWidgetsWithLeakTracking;
• Updates page_route_builder_test.dart to use testWidgetsWithLeakTracking;
• Updates page_storage_test.dart to use testWidgetsWithLeakTracking;
• Updates page_transitions_test.dart to use testWidgetsWithLeakTracking;
• Updates page_view_test.dart to use testWidgetsWithLeakTracking;
• Updates pageable_list_test.dart to use testWidgetsWithLeakTracking;
• Updates parent_data_test.dart to use testWidgetsWithLeakTracking;
• Updates performance_overlay_test.dart to use testWidgetsWithLeakTracking;
• Updates physical_model_test.dart to use testWidgetsWithLeakTracking;
• Updates placeholder_test.dart to use testWidgetsWithLeakTracking;
• Updates platform_menu_bar_test.dart to use testWidgetsWithLeakTracking.

Pre-launch Checklist

• I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
• I read the [Tree Hygiene] wiki page, which explains my responsibilities.
• I read and followed the [Flutter Style Guide], including [Features we expect every widget to implement].
• I signed the [CLA].
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is [test-exempt].
• All existing and new tests are passing.

[ksokolovskyi]

cc @polina-c

[auto-submit]

auto label is removed for flutter/flutter/134884, due to This PR has not met approval requirements for merging. You are not a member of flutter-hackers and need 1 more review(s) in order to merge this PR.

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[ksokolovskyi]

@polina-c thanks for the review!