Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web.Extensions/ui/AppLevelCompilationSectionCache.cs

@@ -0,0 +1,50 @@
+//------------------------------------------------------------------------------
+// <copyright file="AppLevelCompilationSectionCache.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+ 
+namespace System.Web.UI {
+    using System;
+    using System.Configuration;
+    using System.Security;
+    using System.Security.Permissions;
+    using System.Web.Configuration;
+
+    // The compilation section can be defined below the application level, but ScriptManager only considers the
+    // application-level debug setting.
+    internal sealed class AppLevelCompilationSectionCache : ICompilationSection {
+        private static readonly AppLevelCompilationSectionCache _instance = new AppLevelCompilationSectionCache();
+
+        // Value is cached statically, because AppLevelCompilationSectionCache is a Singleton.
+        private bool? _debug;
+
+        private AppLevelCompilationSectionCache() {
+        }
+
+        public static AppLevelCompilationSectionCache Instance {
+            get {
+                return _instance;
+            }
+        }
+
+        public bool Debug {
+            get {
+                if (_debug == null) {
+                    _debug = GetDebugFromConfig();
+                }
+                return _debug.Value;
+            }
+        }
+
+        [
+        ConfigurationPermission(SecurityAction.Assert, Unrestricted = true),
+        SecuritySafeCritical(),
+        ]
+        private static bool GetDebugFromConfig() {
+            CompilationSection section =
+                (CompilationSection)WebConfigurationManager.GetWebApplicationSection("system.web/compilation");
+            return section.Debug;
+        }
+    }
+}