Added new failing conformance test to Ruby, PHP, and C#.

conformance/failure_list_php.txt

diff --git a/conformance/failure_list_php.txt b/conformance/failure_list_php.txt
index 7ee5b9a..70c668a 100644
--- a/conformance/failure_list_php.txt
+++ b/conformance/failure_list_php.txt
@@ -61,6 +61,7 @@
 Recommended.Proto3.ProtobufInput.ValidDataRepeated.UINT64.PackedInput.PackedOutput.ProtobufOutput
 Recommended.Proto3.ProtobufInput.ValidDataRepeated.UINT64.UnpackedInput.DefaultOutput.ProtobufOutput
 Recommended.Proto3.ProtobufInput.ValidDataRepeated.UINT64.UnpackedInput.PackedOutput.ProtobufOutput
+Required.Proto2.JsonInput.StoresDefaultPrimitive.Validator
 Required.Proto3.JsonInput.DoubleFieldTooSmall
 Required.Proto3.JsonInput.FloatFieldTooLarge
 Required.Proto3.JsonInput.FloatFieldTooSmall
@@ -75,8 +76,8 @@
 Required.Proto3.JsonInput.Uint64FieldNotInteger
 Required.Proto3.ProtobufInput.RepeatedScalarMessageMerge.JsonOutput
 Required.Proto3.ProtobufInput.RepeatedScalarMessageMerge.ProtobufOutput
+Required.Proto3.ProtobufInput.ValidDataOneof.MESSAGE.Merge.JsonOutput
+Required.Proto3.ProtobufInput.ValidDataOneof.MESSAGE.Merge.ProtobufOutput
 Required.Proto3.ProtobufInput.ValidDataRepeated.FLOAT.PackedInput.JsonOutput
 Required.Proto3.ProtobufInput.ValidDataRepeated.FLOAT.UnpackedInput.JsonOutput
 Required.Proto3.ProtobufInput.ValidDataScalar.FLOAT[2].JsonOutput
-Required.Proto3.ProtobufInput.ValidDataOneof.MESSAGE.Merge.JsonOutput
-Required.Proto3.ProtobufInput.ValidDataOneof.MESSAGE.Merge.ProtobufOutput