Imported Upstream version 4.3.2.467

Former-commit-id: 9c2cb47f45fa221e661ab616387c9cda183f283d

mcs/class/System.Threading.Tasks.Dataflow/CoreFxSources/Base/ITargetBlock.cs

@@ -0,0 +1,24 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+// =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
+//
+// ITargetBlock.cs
+//
+//
+// The base interface for all target blocks.
+//
+// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+
+namespace System.Threading.Tasks.Dataflow
+{
+    /// <summary>Represents a dataflow block that is a target for data.</summary>
+    /// <typeparam name="TInput">Specifies the type of data accepted by the <see cref="ITargetBlock{TInput}"/>.</typeparam>
+    public interface ITargetBlock<in TInput> : IDataflowBlock
+    {
+        // IMPLEMENT EXPLICITLY
+
+        /// <include file='XmlDocs/CommonXmlDocComments.xml' path='CommonXmlDocComments/Targets/Member[@name="OfferMessage"]/*' />
+        DataflowMessageStatus OfferMessage(DataflowMessageHeader messageHeader, TInput messageValue, ISourceBlock<TInput> source, Boolean consumeToAccept);
+    }
+}