Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs

Index: third_party/protobuf/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
diff --git a/third_party/protobuf/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs b/third_party/protobuf/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
deleted file mode 100644
index d51ee5261d3cece6de9fde4ab19049671fa997fa..0000000000000000000000000000000000000000
--- a/third_party/protobuf/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
+++ /dev/null
@@ -1,127 +0,0 @@
-#region Copyright notice and license
-// Protocol Buffers - Google's data interchange format
-// Copyright 2015 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#endregion
-
-using System.Collections.Generic;
-using System.Collections.ObjectModel;
-using Google.Protobuf.Compatibility;
-
-namespace Google.Protobuf.Reflection
-{
-    /// <summary>
-    /// Describes a "oneof" field collection in a message type: a set of
-    /// fields of which at most one can be set in any particular message.
-    /// </summary>
-    public sealed class OneofDescriptor : DescriptorBase
-    {
-        private readonly OneofDescriptorProto proto;
-        private MessageDescriptor containingType;
-        private IList<FieldDescriptor> fields;
-        private readonly OneofAccessor accessor;
-
-        internal OneofDescriptor(OneofDescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int index, string clrName)
-            : base(file, file.ComputeFullName(parent, proto.Name), index)
-        {
-            this.proto = proto;
-            containingType = parent;
-
-            file.DescriptorPool.AddSymbol(this);
-            accessor = CreateAccessor(clrName);
-        }
-
-        /// <summary>
-        /// The brief name of the descriptor's target.
-        /// </summary>
-        public override string Name { get { return proto.Name; } }
-
-        /// <summary>
-        /// Gets the message type containing this oneof.
-        /// </summary>
-        /// <value>
-        /// The message type containing this oneof.
-        /// </value>
-        public MessageDescriptor ContainingType
-        {
-            get { return containingType; }
-        }
-
-        /// <summary>
-        /// Gets the fields within this oneof, in declaration order.
-        /// </summary>
-        /// <value>
-        /// The fields within this oneof, in declaration order.
-        /// </value>
-        public IList<FieldDescriptor> Fields { get { return fields; } }
-
-        /// <summary>
-        /// Gets an accessor for reflective access to the values associated with the oneof
-        /// in a particular message.
-        /// </summary>
-        /// <value>
-        /// The accessor used for reflective access, or <c>null</c> if reflection is not
-        /// supported by this descriptor.
-        /// </value>
-        public OneofAccessor Accessor { get { return accessor; } }
-
-        internal void CrossLink()
-        {
-            List<FieldDescriptor> fieldCollection = new List<FieldDescriptor>();
-            foreach (var field in ContainingType.Fields.InDeclarationOrder())
-            {
-                if (field.ContainingOneof == this)
-                {
-                    fieldCollection.Add(field);
-                }
-            }
-            fields = new ReadOnlyCollection<FieldDescriptor>(fieldCollection);
-        }
-
-        private OneofAccessor CreateAccessor(string clrName)
-        {
-            if (containingType.GeneratedType == null || clrName == null)
-            {
-                return null;
-            }
-            var caseProperty = containingType.GeneratedType.GetProperty(clrName + "Case");
-            if (caseProperty == null)
-            {
-                throw new DescriptorValidationException(this, "Property " + clrName + "Case not found in " + containingType.GeneratedType);
-            }
-            var clearMethod = containingType.GeneratedType.GetMethod("Clear" + clrName);
-            if (clearMethod == null)
-            {
-                throw new DescriptorValidationException(this, "Method Clear" + clrName + " not found in " + containingType.GeneratedType);
-            }
-
-            return new OneofAccessor(caseProperty, clearMethod, this);
-        }
-    }
-}