Conditional extensions in serialization, Removed usages of extensions methods from unit tests
diff --git a/src/ProtocolBuffers.Test/TestWriterFormatJson.cs b/src/ProtocolBuffers.Test/TestWriterFormatJson.cs
index 1a1a480..98215eb 100644
--- a/src/ProtocolBuffers.Test/TestWriterFormatJson.cs
+++ b/src/ProtocolBuffers.Test/TestWriterFormatJson.cs
@@ -15,7 +15,8 @@
         {

             TestXmlMessage.Builder builder = TestXmlMessage.CreateBuilder();

 

-            builder.MergeFromJson(@"{""valid"":true}");

+            //3.5: builder.MergeFromJson(@"{""valid"":true}");

+            Extensions.MergeFromJson(builder, @"{""valid"":true}");

             

             TestXmlMessage message = builder.Build();

             Assert.AreEqual(true, message.Valid);

@@ -29,7 +30,8 @@
                 .SetValid(true)

                 .Build();

 

-            string json = message.ToJson();

+            //3.5: string json = message.ToJson();

+            string json = Extensions.ToJson(message);

 

             Assert.AreEqual(@"{""valid"":true}", json);

         }

@@ -100,9 +102,9 @@
         public void TestToJsonParseFromJson()

         {

             TestAllTypes msg = new TestAllTypes.Builder().SetDefaultBool(true).Build();

-            string json = msg.ToJson();

+            string json = Extensions.ToJson(msg);

             Assert.AreEqual("{\"default_bool\":true}", json);

-            TestAllTypes copy = new TestAllTypes.Builder().MergeFromJson(json).Build();

+            TestAllTypes copy = Extensions.MergeFromJson(new TestAllTypes.Builder(), json).Build();

             Assert.IsTrue(copy.HasDefaultBool && copy.DefaultBool);

             Assert.AreEqual(msg, copy);

         }

@@ -111,9 +113,9 @@
         public void TestToJsonParseFromJsonReader()

         {

             TestAllTypes msg = new TestAllTypes.Builder().SetDefaultBool(true).Build();

-            string json = msg.ToJson();

+            string json = Extensions.ToJson(msg);

             Assert.AreEqual("{\"default_bool\":true}", json);

-            TestAllTypes copy = new TestAllTypes.Builder().MergeFromJson(new StringReader(json)).Build();

+            TestAllTypes copy = Extensions.MergeFromJson(new TestAllTypes.Builder(), new StringReader(json)).Build();

             Assert.IsTrue(copy.HasDefaultBool && copy.DefaultBool);

             Assert.AreEqual(msg, copy);

         }

@@ -429,7 +431,7 @@
             StringBuilder sb = new StringBuilder(8192);

             for (int i = 0; i < 80; i++)

                 sb.Append("{\"child\":");

-            TestXmlRescursive msg = new TestXmlRescursive.Builder().MergeFromJson(sb.ToString()).Build();

+            TestXmlRescursive msg = Extensions.MergeFromJson(new TestXmlRescursive.Builder(), sb.ToString()).Build();

         }

         [Test, ExpectedException(typeof(FormatException))]

         public void FailWithEmptyText()