Extracted ICodedInputStream interface
diff --git a/src/ProtocolBuffers/CodedInputStream.cs b/src/ProtocolBuffers/CodedInputStream.cs
index 92e547f..74fa947 100644
--- a/src/ProtocolBuffers/CodedInputStream.cs
+++ b/src/ProtocolBuffers/CodedInputStream.cs
@@ -58,7 +58,7 @@
     /// TODO(jonskeet): Consider whether recursion and size limits shouldn't be readonly,

     /// set at construction time.

     /// </remarks>

-    public sealed partial class CodedInputStream

+    public sealed partial class CodedInputStream : ICodedInputStream

     {

         private readonly byte[] buffer;

         private int bufferSize;