Change required for Unity builds

csharp/Facebook.CSSLayout/CSSNode.Create.cs

@@ -19,6 +19,7 @@ namespace UnityEngine.CSSLayout
     internal partial class CSSNode
 // END_UNITY
     {
+#if ENABLE_CS_OPT_ARGS // Optional C# arguments are not supported by some Unity builds
         public static CSSNode Create(
             CSSDirection? styleDirection = null,
             CSSFlexDirection? flexDirection = null,
@@ -241,5 +242,6 @@ namespace UnityEngine.CSSLayout
 
             return node;
         }
+#endif //ENABLE_CS_OPT_ARGS
     }
 }

csharp/tests/Facebook.CSSLayout/CSSLayoutRoundingTest.cs

@@ -11,8 +11,12 @@
 
 using System;
 using NUnit.Framework;
+// BEGIN-UNITY
+using UnityEngine.CSSLayout;
 
-namespace Facebook.CSSLayout
+// namespace Facebook.CSSLayout
+// END-UNITY
+namespace CSSLayoutTests
 {
     [TestFixture]
     public class CSSLayoutRoundingTest

csharp/tests/Facebook.CSSLayout/CSSNodeCreateTest.cs

@@ -20,6 +20,7 @@ using UnityEngine.CSSLayout;
 namespace CSSLayoutTests
 // END-UNITY
 {
+#if ENABLE_CS_OPT_ARGS // Optional C# arguments are not supported by some Unity builds
     [TestFixture]
     public class CSSNodeCreateTest
     {
@@ -145,4 +146,5 @@ namespace CSSLayoutTests
             Assert.AreEqual(26, node.MaxHeight);
         }
     }
+#endif //ENABLE_CS_OPT_ARGS
 }