Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

mcs/class/referencesource/mscorlib/system/io/binaryreader.cs

@@ -23,6 +23,7 @@ namespace System.IO {
     using System.Globalization;
     using System.Diagnostics.Contracts;
     using System.Security;
+    using System.Buffers.Binary;
 
 [System.Runtime.InteropServices.ComVisible(true)]
     public class BinaryReader : IDisposable
@@ -243,6 +244,12 @@ namespace System.IO {
             try {
                 int[] ints = new int[4];
                 Buffer.BlockCopy(m_buffer, 0, ints, 0, 16);
+                if (!BitConverter.IsLittleEndian) {
+                    // We need to reverse the ints on BE
+                    for (int i = 0; i < 4; i++) {
+                         ints[i] = BinaryPrimitives.ReverseEndianness(ints[i]);
+                    }
+                }
                 return new decimal(ints);
             }
             catch (ArgumentException e) {