Fix issue 10 - check serialized size before writing to stream
diff --git a/src/ProtocolBuffers/DescriptorProtos/CSharpOptions.cs b/src/ProtocolBuffers/DescriptorProtos/CSharpOptions.cs
index b589a60..a662b1a 100644
--- a/src/ProtocolBuffers/DescriptorProtos/CSharpOptions.cs
+++ b/src/ProtocolBuffers/DescriptorProtos/CSharpOptions.cs
@@ -169,6 +169,7 @@
     }
     
     public override void WriteTo(pb::CodedOutputStream output) {
+      int size = SerializedSize;
       if (HasNamespace) {
         output.WriteString(1, Namespace);
       }
@@ -571,6 +572,7 @@
     }
     
     public override void WriteTo(pb::CodedOutputStream output) {
+      int size = SerializedSize;
       if (HasPropertyName) {
         output.WriteString(1, PropertyName);
       }