Repository: flutter
Issue: Blur filter isn't clipped when using border radius
Labels: platform-android,platform-ios,engine,customer: crowd,a: platform-views,c: rendering,has reproducible steps,P2,found in release: 3.3,found in release: 3.6,team-ios,triaged-ios

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## Steps to Reproduce

<!-- Please include full steps to reproduce so that we can reproduce the problem. -->

1. [GitHub repo](https://github.com/erikkiralj1/flutter_platform_blur) with reproducible example
2. Run the app on iOS device, preferably iOS simulator

**Expected results:** <!-- what did you want to see? -->
When adding a border radius to a widget, blur should be cut of to follow the radius of the widget

**Actual results:** <!-- what did you see? -->
When adding a border radius to a widget, the blur stays the original size of the widget without the border radius
<details>
<summary>Code sample</summary>

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```dart
// BlurredBlock.dart
// Container as a BackdropFilter child wrapped in ClipRect that has a given border radius 
return ClipRect(
      child: BackdropFilter(
        filter: ImageFilter.blur(sigmaX: 10.0, sigmaY: 10.0),
        child: Container(
          width: 800,
          height: 800,
          decoration: BoxDecoration(
            color: Colors.black.withOpacity(0.5),
            borderRadius: BorderRadius.circular(500),
          ),
          child: const Center(
            child: Text('Blurred block 1'),
          ),
        ),
      ),
    );
```

```dart
// main.dart
// Renders Stack with Google Maps widget and BlurredBlock widget positioned on top of it in the center
 const Center(
              child: BlurredBlock(),
            )
```
</details>

<details>
  <summary>Logs</summary>

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```
[✓] Flutter (Channel master, 3.5.0-12.0.pre.175, on macOS 13.0 22A380 darwin-x64, locale en-HR)
    • Flutter version 3.5.0-12.0.pre.175 on channel master at /Users/erikkiralj/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 92f10ed712 (2 weeks ago), 2022-11-08 17:57:52 -0800
    • Engine revision e7d7edab98
    • Dart version 2.19.0 (build 2.19.0-374.0.dev)
    • DevTools version 2.19.0

[✓] Android toolchain - develop for Android devices (Android SDK version 32.0.0)
    • Android SDK at /Users/erikkiralj/Library/Android/sdk
    • Platform android-33, build-tools 32.0.0
    • Java binary at: /Users/erikkiralj/Library/Application Support/JetBrains/Toolbox/apps/AndroidStudio/ch-0/213.7172.25.2113.9123335/Android Studio.app/Contents/jre/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 11.0.13+0-b1751.21-8125866)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14B47b
    • CocoaPods version 1.11.3

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2021.3)
    • Android Studio at /Users/erikkiralj/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)

[✓] Android Studio (version 2021.2)
    • Android Studio at /Users/erikkiralj/Library/Application Support/JetBrains/Toolbox/apps/AndroidStudio/ch-0/212.5712.43.2112.8815526/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 11.0.12+0-b1504.28-7817840)

[✓] VS Code (version 1.73.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.52.0

[✓] Connected device (3 available)
    • iPad Pro (12.9-inch) (6th generation) (mobile) • ACDD46C2-E0C9-4F97-8E7C-DF60FC3EDF80 • ios            • com.apple.CoreSimulator.SimRuntime.iOS-16-1 (simulator)
    • macOS (desktop)                                • macos                                • darwin-x64     • macOS 13.0 22A380 darwin-x64
    • Chrome (web)                                   • chrome                               • web-javascript • Google Chrome 107.0.5304.110

[✓] HTTP Host Availability
    • All required HTTP hosts are available

• No issues found!

```

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```
```

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```
```

</details>

**Screenshot:**

![Simulator Screen Shot - iPad Pro (12 9-inch) (6th generation) - 2022-11-23 at 14 18 40](https://user-images.githubusercontent.com/94460559/203571891-569cc2cc-4df8-4142-b72a-377c4388e77e.png)