Resurrect ArchitectureSensitiveAttribute

Removal was backed out in SD:712734

src/System.Management.Automation/map.json

@@ -472,6 +472,7 @@
     "monad/src/engine/resources/Authenticode.resx":  "resources/Authenticode.resx",
     "monad/src/engine/COM/ComUtil.cs":  "engine/COM/ComUtil.cs",
     "monad/src/engine/hostifaces/MshHostUserInterface.cs":  "engine/hostifaces/MshHostUserInterface.cs",
+    "monad/src/utils/ArchitectureSensitiveAttribute.cs":  "utils/ArchitectureSensitiveAttribute.cs",
     "monad/src/engine/DriveInterfaces.cs":  "engine/DriveInterfaces.cs",
     "monad/src/engine/ComInterop/Errors.cs":  "engine/ComInterop/Errors.cs",
     "monad/src/singleshell/config/MshConsoleInfo.cs":  "singleshell/config/MshConsoleInfo.cs",

src/System.Management.Automation/utils/ArchitectureSensitiveAttribute.cs

@@ -0,0 +1,28 @@
+/********************************************************************++
+Copyright (c) Microsoft Corporation.  All rights reserved.
+--********************************************************************/
+
+using System;
+using System.Reflection;
+
+namespace System.Management.Automation.Internal
+{
+    /// <summary>
+    /// This attribute is used for Design For Testability.
+    /// It should be placed on any method containing code
+    /// which is likely to be sensitive to X86/X64/IA64 issues,
+    /// primarily code which calls DllImports or otherwise uses
+    /// NativeMethods.  This allows us to generate code coverage
+    /// data specific to architecture sensitive code.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Method, AllowMultiple=false)]
+    internal class ArchitectureSensitiveAttribute : Attribute
+    {
+        /// <summary>
+        /// Constructor for the ArchitectureSensitiveAttribute class.
+        /// </summary>
+        internal ArchitectureSensitiveAttribute ()
+        {
+        }
+    }
+}