Move ThemeBinding into UXCore

Author: keveleigh

org.mixedrealitytoolkit.uxcore/Theming.meta

@@ -0,0 +1,23 @@
+{
+    "name": "MixedReality.Toolkit.UXCore.Theming",
+    "rootNamespace": "MixedReality.Toolkit.UX",
+    "references": [
+        "GUID:56255bd5d851a6243b63cb370cfc40b1",
+        "GUID:2238d58cada9b6746a548c6bff32c381"
+    ],
+    "includePlatforms": [],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": true,
+    "defineConstraints": [],
+    "versionDefines": [
+        {
+            "name": "org.mixedrealitytoolkit.theming",
+            "expression": "",
+            "define": "MRTK_THEMING_PRESENT"
+        }
+    ],
+    "noEngineReferences": false
+}

org.mixedrealitytoolkit.uxcore/Theming/MRTK.UXCore.Theming.asmdef

@@ -1,12 +1,17 @@
 // Copyright (c) Mixed Reality Toolkit Contributors
 // Licensed under the BSD 3-Clause
 
+#if MRTK_THEMING_PRESENT
+using MixedReality.Toolkit.Theming;
+#endif
+
 using UnityEngine;
 
-namespace MixedReality.Toolkit.Theming
+namespace MixedReality.Toolkit.UX
 {
     public class ThemeBinding : MonoBehaviour
     {
+#if MRTK_THEMING_PRESENT
         [SerializeField]
         [Tooltip("The theme data source manager.")]
         private ThemeDataSource themeDataSource;
@@ -47,5 +52,6 @@ protected void OnDisable()
                 binder?.Unsubscribe(themeDataSource);
             }
         }
+#endif
     }
 }