fix render target corruption detection.

src/Web/Avalonia.Web.Blazor/BlazorSkiaGpuRenderTarget.cs

@@ -34,20 +34,6 @@ namespace Avalonia.Web.Blazor
             return new BlazorSkiaGpuRenderSession(_blazorSkiaSurface, _renderTarget);
         }
 
-        public bool IsCorrupted
-        {
-            get
-            {
-                if( _blazorSkiaSurface.IsDirty )
-                {
-                    _blazorSkiaSurface.IsDirty = false;
-                    return true;
-                }
-
-                var result = _size.Width != _renderTarget.Width || _size.Height != _renderTarget.Height;
-
-                return result;
-            }
-        }
+        public bool IsCorrupted => _blazorSkiaSurface.Size != _size;
     }
 }

src/Web/Avalonia.Web.Blazor/BlazorSkiaSurface.cs

@@ -26,7 +26,5 @@ namespace Avalonia.Web.Blazor
         public double Scaling { get; set; }
 
         public SKHtmlCanvasInterop.GLInfo GlInfo { get; set; }
-
-        public bool IsDirty { get; set; }
     }
 }

src/Web/Avalonia.Web.Blazor/RazorViewTopLevelImpl.cs

@@ -51,8 +51,6 @@ namespace Avalonia.Web.Blazor
                 if (_currentSurface is { })
                 {
                     _currentSurface.Size = new PixelSize((int)size.Width, (int)size.Height);
-
-                    _currentSurface.IsDirty = true;
                 }
 
                 Resized?.Invoke(newSize, PlatformResizeReason.User);