First cut at new layout
diff --git a/src/ProtocolBuffers/ExtensionInfo.cs b/src/ProtocolBuffers/ExtensionInfo.cs
new file mode 100644
index 0000000..00cf0d0
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+++ b/src/ProtocolBuffers/ExtensionInfo.cs
@@ -0,0 +1,40 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.
+// http://code.google.com/p/protobuf/
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+using Google.ProtocolBuffers.Descriptors;
+
+namespace Google.ProtocolBuffers
+{
+ public sealed class ExtensionInfo {
+ /// <summary>
+ /// The extension's descriptor
+ /// </summary>
+ public FieldDescriptor Descriptor { get; private set; }
+
+ /// <summary>
+ /// A default instance of the extensions's type, if it has a message type,
+ /// or null otherwise.
+ /// </summary>
+ public IMessage DefaultInstance { get; private set; }
+
+ internal ExtensionInfo(FieldDescriptor descriptor) : this(descriptor, null) {
+ }
+
+ internal ExtensionInfo(FieldDescriptor descriptor, IMessage defaultInstance) {
+ Descriptor = descriptor;
+ DefaultInstance = defaultInstance;
+ }
+ }
+}
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