Merge pull request #2196 from jp2masa/matrix-optimization

Removed duplicate call to GetDeterminant

src/Avalonia.Visuals/Matrix.cs

@@ -293,13 +293,13 @@ namespace Avalonia
         /// <returns>The inverted matrix.</returns>
         public Matrix Invert()
         {
-            if (GetDeterminant() == 0)
+            double d = GetDeterminant();
+
+            if (d == 0)
             {
                 throw new InvalidOperationException("Transform is not invertible.");
             }
 
-            double d = GetDeterminant();
-
             return new Matrix(
                 _m22 / d,
                 -_m12 / d,