Make topGap not required for CupertinoSheetTransition - #181269

…ter/flutter#181269)

Roll Flutter from 48c2475 to bfc9041eb118 (173 revisions)

flutter/flutter@48c2475...bfc9041

2026-01-23 [email protected] No longer exiting the application when the RegularWindow is destroyed + resolving the window created promise after runWidget (flutter/flutter#181339)
2026-01-23 [email protected] Remove unnecessary Material import from dialog_test.dart (flutter/flutter#181249)
2026-01-23 [email protected] Roll Skia from 8e516fe6828f to db10db8bd55f (1 revision) (flutter/flutter#181379)
2026-01-23 [email protected] Reset TextFormField to initial value after state change (flutter/flutter#181199)
2026-01-23 [email protected] Roll Dart SDK from 980b2b41d36e to e82d7ad1855e (1 revision) (flutter/flutter#181375)
2026-01-23 [email protected] Roll Skia from 3e86f377d300 to 8e516fe6828f (4 revisions) (flutter/flutter#181370)
2026-01-23 [email protected] Remove unnecessary Material import from sliver_visibility_test (flutter/flutter#181248)
2026-01-23 [email protected] Add bottom navigation bar item semantics label (flutter/flutter#180577)
2026-01-23 [email protected] Make topGap not required for CupertinoSheetTransition (flutter/flutter#181269)
2026-01-23 [email protected] Roll Fuchsia Linux SDK from b4cLyhuxciUC-4zCJ... to n7NohL9DPpEuPjNt9... (flutter/flutter#181365)
2026-01-23 [email protected] Roll Dart SDK from 806f04638561 to 980b2b41d36e (1 revision) (flutter/flutter#181364)
2026-01-23 [email protected] Reland hybrid views test (flutter/flutter#181336)
2026-01-23 [email protected] Revert DropdownMenu non-nullable breaking change (flutter/flutter#181074)
2026-01-23 [email protected] Fix leaks in `flutter_test` tests (flutter/flutter#180879)
2026-01-23 [email protected] Re-enable fragment_shader_tests.dart 'Shader Compiler appropriately pads vec3 uniform arrays' test on Vulkan (flutter/flutter#181292)
2026-01-23 [email protected] [ Tool ] Fix `update-packages` failing due to mismatched dependencies between flutter_tools and the framework (flutter/flutter#181335)
2026-01-23 [email protected] [Impeller] Make dynamically created shader metadata for runtime effects consistent with metadata for built-in shaders (flutter/flutter#181201)
2026-01-23 [email protected] Broaden the applicability of `Color` fix_data rules from flutter/painting.dart (flutter/flutter#181093)
2026-01-23 [email protected] Fixes macOS App.framework not being codesigned or find framework (flutter/flutter#181348)
2026-01-22 [email protected] Roll Fuchsia GN SDK from NAEC5tfgSl8g94nwp... to JLBh4Z9PKsjIJcqDU... (flutter/flutter#181139)
2026-01-22 [email protected] Roll Dart SDK from ab4640ea82e9 to 806f04638561 (2 revisions) (flutter/flutter#181347)
2026-01-22 [email protected] Add ExpansibleController.toggle method. (flutter/flutter#181320)
2026-01-22 [email protected] Fixes Typo in codebase (flutter/flutter#181256)
2026-01-22 [email protected] Roll Skia from 4766615bcc96 to 3e86f377d300 (3 revisions) (flutter/flutter#181346)
2026-01-22 [email protected] Make sure that a Hero doesn't crash in 0x0 environment (flutter/flutter#180954)
2026-01-22 [email protected] Reland "Fix capitalization of the path to FlutterWindowControllerTest.mm in the macOS platform build script" (flutter/flutter#181200)
2026-01-22 [email protected] Roll Skia from 6e9746be8c4a to 4766615bcc96 (3 revisions) (flutter/flutter#181331)
2026-01-22 [email protected] Fix remove material import textfield (flutter/flutter#181254)
2026-01-22 [email protected] Add FlutterFramework as an Xcode SwiftPM local package override (flutter/flutter#179512)
2026-01-22 [email protected] Roll Dart SDK from 7bd4c68b625c to ab4640ea82e9 (1 revision) (flutter/flutter#181324)
2026-01-22 [email protected] Roll Packages from d80c60e to 9010299 (9 revisions) (flutter/flutter#181323)
2026-01-22 [email protected] Roll Dart SDK from 2d53a77adc5d to 7bd4c68b625c (2 revisions) (flutter/flutter#181316)
2026-01-22 [email protected] Roll Skia from 3f6949bc5780 to 6e9746be8c4a (2 revisions) (flutter/flutter#181311)
2026-01-22 [email protected] Roll Skia from ef6efc358b4a to 3f6949bc5780 (2 revisions) (flutter/flutter#181307)
2026-01-22 [email protected] Roll Dart SDK from 5d7c8faf2e41 to 2d53a77adc5d (1 revision) (flutter/flutter#181305)
2026-01-22 [email protected] [Material] update hourFormat to use Dart 3 switch expression (flutter/flutter#181041)
2026-01-22 [email protected] Use null-aware elements in cupertino/nav_bar.dart (flutter/flutter#181237)
2026-01-22 [email protected] Roll Fuchsia Linux SDK from b2KIEXVAlEqImQ9VO... to b4cLyhuxciUC-4zCJ... (flutter/flutter#181297)
2026-01-22 [email protected] Roll pub packages (flutter/flutter#181295)
2026-01-22 [email protected] Enables fragment shader test for impeller (fixes mat2 on vulkan) (flutter/flutter#181013)
2026-01-21 [email protected] Roll Dart SDK from 366200db1aa1 to 5d7c8faf2e41 (4 revisions) (flutter/flutter#181290)
2026-01-21 [email protected] Roll Skia from b5ec89e31f59 to ef6efc358b4a (19 revisions) (flutter/flutter#181289)
2026-01-21 [email protected] fix description for semantics finders (flutter/flutter#181214)
2026-01-21 [email protected] Make sure that an Icon doesn't crash in 0x0 environment (flutter/flutter#181021)
2026-01-21 [email protected] Make sure that a GridPaper doesn't crash in 0x0 environment (flutter/flutter#180906)
2026-01-21 [email protected] Bring Linux coverage out of bringup (flutter/flutter#181280)
...

This PR cherrypicks #181269 into beta. This is needed to address a breakage.

**Impacted Users:** Apps that directly use `CupertinoSheetTransition `.

**Impact Description:** Can not compile.

**Workaround:** Yes. They need to add `topGap: 0.08` to the constructor.

**Risk:** Low. This PR loosens the API, and reverts the behavior to that before #171348.

**Test Coverage:** Yes. The widget has high test coverage.

**Validation Steps:** The PR compiles and tests pass. `sheet_test.dart` contains constructors that do not specify `topGap` in the same way as existing apps.

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flutter#171348 made a breaking change that was missed by adding a required
parameter to a public class. See this
[comment](flutter#171348 (comment)).

This PR removes the required parameter and has the value default to the
same value used elsewhere.


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Co-authored-by: Tong Mu <[email protected]>

…181371)

)

Roll Flutter from 48c2475 to bfc9041eb118 (173 revisions)

flutter/flutter@48c2475...bfc9041

2026-01-23 [email protected] No longer exiting the application when the RegularWindow is destroyed + resolving the window created promise after runWidget (flutter/flutter#181339)
2026-01-23 [email protected] Remove unnecessary Material import from dialog_test.dart (flutter/flutter#181249)
2026-01-23 [email protected] Roll Skia from 8e516fe6828f to db10db8bd55f (1 revision) (flutter/flutter#181379)
2026-01-23 [email protected] Reset TextFormField to initial value after state change (flutter/flutter#181199)
2026-01-23 [email protected] Roll Dart SDK from 980b2b41d36e to e82d7ad1855e (1 revision) (flutter/flutter#181375)
2026-01-23 [email protected] Roll Skia from 3e86f377d300 to 8e516fe6828f (4 revisions) (flutter/flutter#181370)
2026-01-23 [email protected] Remove unnecessary Material import from sliver_visibility_test (flutter/flutter#181248)
2026-01-23 [email protected] Add bottom navigation bar item semantics label (flutter/flutter#180577)
2026-01-23 [email protected] Make topGap not required for CupertinoSheetTransition (flutter/flutter#181269)
2026-01-23 [email protected] Roll Fuchsia Linux SDK from b4cLyhuxciUC-4zCJ... to n7NohL9DPpEuPjNt9... (flutter/flutter#181365)
2026-01-23 [email protected] Roll Dart SDK from 806f04638561 to 980b2b41d36e (1 revision) (flutter/flutter#181364)
2026-01-23 [email protected] Reland hybrid views test (flutter/flutter#181336)
2026-01-23 [email protected] Revert DropdownMenu non-nullable breaking change (flutter/flutter#181074)
2026-01-23 [email protected] Fix leaks in `flutter_test` tests (flutter/flutter#180879)
2026-01-23 [email protected] Re-enable fragment_shader_tests.dart 'Shader Compiler appropriately pads vec3 uniform arrays' test on Vulkan (flutter/flutter#181292)
2026-01-23 [email protected] [ Tool ] Fix `update-packages` failing due to mismatched dependencies between flutter_tools and the framework (flutter/flutter#181335)
2026-01-23 [email protected] [Impeller] Make dynamically created shader metadata for runtime effects consistent with metadata for built-in shaders (flutter/flutter#181201)
2026-01-23 [email protected] Broaden the applicability of `Color` fix_data rules from flutter/painting.dart (flutter/flutter#181093)
2026-01-23 [email protected] Fixes macOS App.framework not being codesigned or find framework (flutter/flutter#181348)
2026-01-22 [email protected] Roll Fuchsia GN SDK from NAEC5tfgSl8g94nwp... to JLBh4Z9PKsjIJcqDU... (flutter/flutter#181139)
2026-01-22 [email protected] Roll Dart SDK from ab4640ea82e9 to 806f04638561 (2 revisions) (flutter/flutter#181347)
2026-01-22 [email protected] Add ExpansibleController.toggle method. (flutter/flutter#181320)
2026-01-22 [email protected] Fixes Typo in codebase (flutter/flutter#181256)
2026-01-22 [email protected] Roll Skia from 4766615bcc96 to 3e86f377d300 (3 revisions) (flutter/flutter#181346)
2026-01-22 [email protected] Make sure that a Hero doesn't crash in 0x0 environment (flutter/flutter#180954)
2026-01-22 [email protected] Reland "Fix capitalization of the path to FlutterWindowControllerTest.mm in the macOS platform build script" (flutter/flutter#181200)
2026-01-22 [email protected] Roll Skia from 6e9746be8c4a to 4766615bcc96 (3 revisions) (flutter/flutter#181331)
2026-01-22 [email protected] Fix remove material import textfield (flutter/flutter#181254)
2026-01-22 [email protected] Add FlutterFramework as an Xcode SwiftPM local package override (flutter/flutter#179512)
2026-01-22 [email protected] Roll Dart SDK from 7bd4c68b625c to ab4640ea82e9 (1 revision) (flutter/flutter#181324)
2026-01-22 [email protected] Roll Packages from d80c60e to 9010299 (9 revisions) (flutter/flutter#181323)
2026-01-22 [email protected] Roll Dart SDK from 2d53a77adc5d to 7bd4c68b625c (2 revisions) (flutter/flutter#181316)
2026-01-22 [email protected] Roll Skia from 3f6949bc5780 to 6e9746be8c4a (2 revisions) (flutter/flutter#181311)
2026-01-22 [email protected] Roll Skia from ef6efc358b4a to 3f6949bc5780 (2 revisions) (flutter/flutter#181307)
2026-01-22 [email protected] Roll Dart SDK from 5d7c8faf2e41 to 2d53a77adc5d (1 revision) (flutter/flutter#181305)
2026-01-22 [email protected] [Material] update hourFormat to use Dart 3 switch expression (flutter/flutter#181041)
2026-01-22 [email protected] Use null-aware elements in cupertino/nav_bar.dart (flutter/flutter#181237)
2026-01-22 [email protected] Roll Fuchsia Linux SDK from b2KIEXVAlEqImQ9VO... to b4cLyhuxciUC-4zCJ... (flutter/flutter#181297)
2026-01-22 [email protected] Roll pub packages (flutter/flutter#181295)
2026-01-22 [email protected] Enables fragment shader test for impeller (fixes mat2 on vulkan) (flutter/flutter#181013)
2026-01-21 [email protected] Roll Dart SDK from 366200db1aa1 to 5d7c8faf2e41 (4 revisions) (flutter/flutter#181290)
2026-01-21 [email protected] Roll Skia from b5ec89e31f59 to ef6efc358b4a (19 revisions) (flutter/flutter#181289)
2026-01-21 [email protected] fix description for semantics finders (flutter/flutter#181214)
2026-01-21 [email protected] Make sure that an Icon doesn't crash in 0x0 environment (flutter/flutter#181021)
2026-01-21 [email protected] Make sure that a GridPaper doesn't crash in 0x0 environment (flutter/flutter#180906)
2026-01-21 [email protected] Bring Linux coverage out of bringup (flutter/flutter#181280)
...