Refactoring of CodedInputStream.Read??? to use boolean return with out param.
diff --git a/src/ProtocolBuffers/GeneratedBuilder.cs b/src/ProtocolBuffers/GeneratedBuilder.cs
index b44cd63..699320a 100644
--- a/src/ProtocolBuffers/GeneratedBuilder.cs
+++ b/src/ProtocolBuffers/GeneratedBuilder.cs
@@ -116,7 +116,7 @@
         /// <returns>true unless the tag is an end-group tag</returns>

         [CLSCompliant(false)]

         protected virtual bool ParseUnknownField(CodedInputStream input, UnknownFieldSet.Builder unknownFields,

-                                                 ExtensionRegistry extensionRegistry, uint tag)

+                                                 ExtensionRegistry extensionRegistry, uint tag, string fieldName)

         {

             return unknownFields.MergeFieldFrom(tag, input);

         }