Repository: flutter
Issue: [Impeller] Unsharp circle border when using impeller
Labels: platform-ios,engine,has reproducible steps,P2,e: impeller,found in release: 3.7,found in release: 3.9,team-engine,triaged-engine

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When trying to render a container with BoxDecoration `shape: BoxShape.circle` it will not look very sharp with impeller. 

It is very sharp when running without impeller.

**Target Platform:** iOS
**Target OS version:** 16.3.1
**Device:** Iphone 12 pro

## Steps to Reproduce

<!-- Please include full steps to reproduce so that we can reproduce the problem. -->

1. Execute `flutter run --enable-impeller` on the code sample <!-- (see "Code sample" section below) -->

**Expected results:** <!-- what did you want to see? -->

The black border should be a sharp "high resolution" circle.

**Actual results:** <!-- what did you see? -->

The border is unsharp/noisy when rendered with impeller.

Running the code sample without impeller the circle border is sharp. 

Without impeller:
<img src="https://user-images.githubusercontent.com/39732540/222172814-8d0208c5-9fb0-4ed2-be13-59e9b400a33b.png" width="40%">

With impeller:
(look how unsharp the black border circle is on the smallest circle)
<img src="https://user-images.githubusercontent.com/39732540/222172991-271f60c5-8d0d-40db-bc4c-f1c2e22ff4c9.png" width="40%">

<details>
<summary>Code sample</summary>

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```dart
import 'package:flutter/material.dart';

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Unsharp circle border with impeller'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: const [
          Center(child: LetterCircle(letter: 'A', width: 48, fontSize: 18)),
          SizedBox(height: 12),
          Center(child: LetterCircle(letter: 'A', width: 24, fontSize: 16)),
          SizedBox(height: 12),
          Center(child: LetterCircle(letter: 'A', width: 18, fontSize: 12)),
        ],
      ),
    );
  }
}

class LetterCircle extends StatelessWidget {
  final String letter;
  final double width;
  final double fontSize;

  const LetterCircle({
    super.key,
    required this.letter,
    required this.width,
    required this.fontSize,
  });

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      height: width,
      width: width,
      child: Container(
        decoration: const BoxDecoration(
          color: Colors.orange,
          shape: BoxShape.circle,
          border: Border.fromBorderSide(BorderSide(color: Colors.black)),
        ),
        child: Center(
          child: Text(
            letter,
            style: TextStyle(
              fontSize: fontSize,
              color: Colors.black,
              fontWeight: FontWeight.bold,
            ),
            textAlign: TextAlign.center,
            textScaleFactor: 1.0,
          ),
        ),
      ),
    );
  }
}

void main() {
  runApp(
    const MaterialApp(
      home: MyApp(),
    ),
  );
}

```

</details>

<details>
  <summary>Logs</summary>

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```
```

<!--
     Run `flutter analyze` and attach any output of that command below.
     If there are any analysis errors, try resolving them before filing this issue.
-->

```
No issues found! (ran in 1.0s)
```

<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
[✓] Flutter (Channel stable, 3.7.5, on macOS 13.2.1 22D68 darwin-arm64, locale
    nb-NO)
    • Flutter version 3.7.5 on channel stable at
      /opt/homebrew/Caskroom/flutter/3.3.9/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision c07f788888 (7 days ago), 2023-02-22 17:52:33 -0600
    • Engine revision 0f359063c4
    • Dart version 2.19.2
    • DevTools version 2.20.1

[!] Android toolchain - develop for Android devices (Android SDK version 33.0.1)
    • Android SDK at /Users/xxxx/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for
      more details.

[✓] Xcode - develop for iOS and macOS (Xcode 14.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14C18
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2021.3)
    • Android Studio at /Users/xxxx/Library/Application
      Support/JetBrains/Toolbox/apps/AndroidStudio/ch-0/213.7172.25.2113.9123335
      /Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build
      11.0.13+0-b1751.21-8125866)
```

</details>


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