Merge pull request #392 from Unity-Technologies/ut-585_Fixing_2018_2_deprecated_timeline_code_breaks_2018_1

UT-585 Fixing 2018.2 deprecated timeline code, breaks 2018.1

Author: vkovec

Assets/com.unity.formats.fbx/Editor/Scripts/FbxExporter.cs

@@ -3588,7 +3588,13 @@ protected static bool ExportSingleEditorClip(Object editorClipSelected)
 					object selClipItem = editorClipSelected.GetType().GetProperty("item").GetValue(editorClipSelected, null);
 					object selClipItemParentTrack = selClipItem.GetType().GetProperty("parentTrack").GetValue(selClipItem, null);
 					AnimationTrack editorClipAnimationTrack = selClipItemParentTrack as AnimationTrack;
-                    Object animationTrackObject = UnityEditor.Timeline.TimelineEditor.inspectedDirector.GetGenericBinding (editorClipAnimationTrack);
+
+#if UNITY_2018_2_OR_NEWER
+                    Object animationTrackObject = UnityEditor.Timeline.TimelineEditor.inspectedDirector.GetGenericBinding(editorClipAnimationTrack);
+#else // UNITY_2018_2_OR_NEWER
+                    Object animationTrackObject = UnityEditor.Timeline.TimelineEditor.playableDirector.GetGenericBinding(editorClipAnimationTrack);
+#endif // UNITY_2018_2_OR_NEWER
+
                     GameObject animationTrackGO = null;
                     if (animationTrackObject is GameObject)
                     {