fix nits.

src/Avalonia.Visuals/Media/Imaging/WriteableBitmap.cs

@@ -59,7 +59,7 @@ namespace Avalonia.Media.Imaging
         /// <param name="width">The desired width of the resulting bitmap.</param>
         /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should any scaling be required.</param>
         /// <returns>An instance of the <see cref="Bitmap"/> class.</returns>
-        public static Bitmap DecodeToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
+        public new static WriteableBitmap DecodeToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             var ri = AvaloniaLocator.Current.GetService<IPlatformRenderInterface>();
 
@@ -74,7 +74,7 @@ namespace Avalonia.Media.Imaging
         /// <param name="height">The desired height of the resulting bitmap.</param>
         /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should any scaling be required.</param>
         /// <returns>An instance of the <see cref="Bitmap"/> class.</returns>
-        public static Bitmap DecodeToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
+        public new static WriteableBitmap DecodeToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality)
         {
             var ri = AvaloniaLocator.Current.GetService<IPlatformRenderInterface>();
 

src/Avalonia.Visuals/Platform/IPlatformRenderInterface.cs

@@ -106,7 +106,7 @@ namespace Avalonia.Platform
         /// <param name="stream">The stream to read the bitmap from.</param> 
         /// <param name="width">The desired width of the resulting bitmap.</param>
         /// <param name="interpolationMode">The <see cref="BitmapInterpolationMode"/> to use should resizing be required.</param>
-        /// <returns>An <see cref="IBitmapImpl"/>.</returns>
+        /// <returns>An <see cref="IWriteableBitmapImpl"/>.</returns>
         IWriteableBitmapImpl LoadWriteableBitmapToWidth(Stream stream, int width, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality);
 
         /// <summary>
@@ -119,14 +119,14 @@ namespace Avalonia.Platform
         IWriteableBitmapImpl LoadWriteableBitmapToHeight(Stream stream, int height, BitmapInterpolationMode interpolationMode = BitmapInterpolationMode.HighQuality);
         
         /// <summary>
-        /// Loads a WriteableBitmap implementation from a file..
+        /// Loads a WriteableBitmap implementation from a file.
         /// </summary>
         /// <param name="fileName">The filename of the bitmap.</param>        
         /// <returns>An <see cref="IBitmapImpl"/>.</returns>
         IWriteableBitmapImpl LoadWriteableBitmap(string fileName);
 
         /// <summary>
-        /// Loads a WriteableBitmap implementation from a file..
+        /// Loads a WriteableBitmap implementation from a file.
         /// </summary>
         /// <param name="stream">The stream to read the bitmap from.</param>        
         /// <returns>An <see cref="IBitmapImpl"/>.</returns>

src/Skia/Avalonia.Skia/WriteableBitmapImpl.cs

@@ -34,7 +34,7 @@ namespace Avalonia.Skia
                 }
 
                 PixelSize = new PixelSize(_bitmap.Width, _bitmap.Height);
-                Dpi = new Vector(96, 96);
+                Dpi = SkiaPlatform.DefaultDpi;
             }
         }
 
@@ -77,7 +77,7 @@ namespace Avalonia.Skia
                 _bitmap = bmp;
 
                 PixelSize = new PixelSize(bmp.Width, bmp.Height);
-                Dpi = new Vector(96, 96);
+                Dpi = SkiaPlatform.DefaultDpi;
             }
         }