fix comments

csharp/src/ProtocolBuffers.Test/FieldPresenceTest.cs

@@ -163,7 +163,7 @@ namespace Google.ProtocolBuffers
         }
 
         [Fact]
-        public void TestSeralizeAndParse()
+        public void TestSerializeAndParse()
         {
             TestAllTypes.Builder builder = TestAllTypes.CreateBuilder();
             builder.SetOptionalInt32(1234);

csharp/src/ProtocolBuffers/Descriptors/FileDescriptor.cs

@@ -56,13 +56,13 @@ namespace Google.ProtocolBuffers.Descriptors
 
         public enum ProtoSyntax
         {
-            PROTO2,
-            PROTO3
+            Proto2,
+            Proto3
         }
 
         public ProtoSyntax Syntax
         {
-            get { return proto.Syntax == "proto3" ? ProtoSyntax.PROTO3 : ProtoSyntax.PROTO2; }
+            get { return proto.Syntax == "proto3" ? ProtoSyntax.Proto3 : ProtoSyntax.Proto2; }
         }
 
         private FileDescriptor(FileDescriptorProto proto, FileDescriptor[] dependencies, DescriptorPool pool, bool allowUnknownDependencies)

csharp/src/ProtocolBuffers/FieldAccess/FieldAccessorTable.cs

@@ -68,7 +68,7 @@ namespace Google.ProtocolBuffers.FieldAccess
         {
             this.descriptor = descriptor;
             accessors = new IFieldAccessor<TMessage, TBuilder>[descriptor.Fields.Count];
-            bool supportFieldPresence = descriptor.File.Syntax == FileDescriptor.ProtoSyntax.PROTO2;
+            bool supportFieldPresence = descriptor.File.Syntax == FileDescriptor.ProtoSyntax.Proto2;
             for (int i = 0; i < accessors.Length; i++)
             {
                 accessors[i] = CreateAccessor(descriptor.Fields[i], propertyNames[i], supportFieldPresence);

csharp/src/ProtocolBuffers/FieldAccess/SinglePrimitiveAccessor.cs

@@ -43,7 +43,6 @@ namespace Google.ProtocolBuffers.FieldAccess
         where TBuilder : IBuilder<TMessage, TBuilder>
     {
         private readonly Type clrType;
-        private readonly FieldDescriptor field;
         private readonly Func<TMessage, object> getValueDelegate;
         private readonly Action<TBuilder, object> setValueDelegate;
         private readonly Func<TMessage, bool> hasDelegate;