Remove exclamation marks

[LongCatIsLooong]

Remove some unnecessary !s in input decorator.

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.

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[justinmc]

LGTM 👍

Thanks for cleaning this up!

[limenote135]

@LongCatIsLooong @justinmc Is there a plan to hotfix this into the stable branch? Many users are facing this issue.

[justinmc]

@limenote135 What is the issue exactly? I want to make sure I understand which of the changes in this PR are unblocking you and in what way.

[limenote135]

@justinmc This fixes issues: #111095, #112046, #111939, #97634.
After upgrading flutter 3.3 from 3.0, this error is reported significantly.

[justinmc]

Perfect, thank you!

@itsjustkevin Are we able to cherry-pick this fix?

[limenote135]

@justinmc @itsjustkevin hi, how is it going?

[DjordjeMancic97]

Hi I am experiencing issue which this PR is supposed to fix. When will this come to stable branch?

Null check operator used on a null value.
at .#0 State.widget (package:flutter/src/widgets/framework.dart:909:26)
at .#1 EditableTextState._value (package:flutter/src/widgets/editable_text.dart:2351:34)
at .#2 EditableTextState.updateEditingValue (package:flutter/src/widgets/editable_text.dart:2084:18)
at .#3 TextInput._handleTextInputInvocation (package:flutter/src/services/text_input.dart:1769:29)
at .#4 DefaultPlatformMenuDelegate._methodCallHandler (package:flutter/src/widgets/platform_menu_bar.dart:461:21)
at .#5 min (dart:math-patch/math_patch.dart:35:21)
at .#6 new Rect.fromPoints (dart:ui/geometry.dart:670:10)
at .#7 TypeTestingStub_MHi__Kua__X0_21928+0x2f
at .#8 DateTime._yearsFromSecondsSinceEpoch (dart:core-patch/date_patch.dart:377:3)
at .#9 SchedulerBinding.scheduleWarmUpFrame. (package:flutter/src/scheduler/binding.dart:899:16)
at .#10 PlatformDispatcher._unpackPointerDataPacket (dart:ui/platfor

[LongCatIsLooong]

@DjordjeMancic97 from the stacktrace this is not the same issue. It may have to do with the platform menu system. Could you open a new issue if there isn't one?

For those on the stable branch, the diff is one line: https://github.com/flutter/flutter/pull/107683/files#diff-f5f93c879cef9a102adbf148583de9f3d9a05f9678fdcad7bde106f62200bb34 so it's an option to patch this locally for the time being.