Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/UI/WebControls/PlaceHolder.cs

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+//------------------------------------------------------------------------------
+// <copyright file="PlaceHolder.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+//------------------------------------------------------------------------------
+
+namespace System.Web.UI.WebControls {
+
+using System;
+using System.ComponentModel;
+using System.Web.UI;
+
+    /// <devdoc>
+    /// <para>Interacts with the parser to build a <see cref='System.Web.UI.WebControls.PlaceHolder'/> control.</para>
+    /// </devdoc>
+    public class PlaceHolderControlBuilder : ControlBuilder {
+ 
+
+       /// <internalonly/>
+       /// <devdoc>
+       ///    <para>Specifies whether white space literals are allowed.</para>
+       /// </devdoc>
+       public override bool AllowWhitespaceLiterals() {
+            return false;
+        }
+    }
+
+// The reason we define this empty override in the WebControls namespace is
+// to expose it as a control that can be used on a page (ASURT 51116)
+// E.g. <asp:placeholder runat=server id=ph1/>
+
+/// <devdoc>
+///    <para>[To be supplied.]</para>
+/// </devdoc>
+    [
+    ControlBuilderAttribute(typeof(PlaceHolderControlBuilder))
+    ]
+    public class PlaceHolder : Control {
+
+        /// <devdoc>
+        ///    <para>Gets and sets a value indicating whether theme is enabled.</para>
+        /// </devdoc>
+        [
+        Browsable(true)
+        ]
+        public override bool EnableTheming {
+            get {
+                return base.EnableTheming;
+            }
+            set {
+                base.EnableTheming = value;
+            }
+        }
+    }
+}