Merge pull request #220 from Unity-Technologies/zgh/fix_orientation_bug

fix: raycastable rect doesn't update when orientation changed

com.unity.uiwidgets/Runtime/engine/raycastable/RaycastManager.cs

             instance.raycastHandlerMap[windowHashCode][widgetHashCode] = new RaycastableRect();
         }
 
+        public static void OnScreenSizeChanged(int windowHashCode) {
+            if (!instance.raycastHandlerMap.ContainsKey(windowHashCode)) return;
+            Dictionary<int, RaycastableRect> raycastableWidgets = RaycastManager.instance.raycastHandlerMap[windowHashCode];
+            foreach (var item in raycastableWidgets) {
+                MarkDirty(item.Key, windowHashCode);
+            }
+        }
+
         public static void MarkDirty(int widgetHashCode, int windowHashCode) {
             D.assert(instance.raycastHandlerMap.ContainsKey(windowHashCode), () =>
                 $"Raycast Handler Map doesn't contain Window {windowHashCode}");

com.unity.uiwidgets/Runtime/engine/raycastable/UIWidgetsRaycastablePanel.cs

             RaycastManager.DisposeWindow(windowHashCode);
         }
 
+        protected override void OnRectTransformDimensionsChange() {
+            base.OnRectTransformDimensionsChange();
+            RaycastManager.OnScreenSizeChanged(windowHashCode);
+        }
+
         public bool IsRaycastLocationValid(Vector2 screenPoint, Camera eventCamera) {
             if (!enabled) {
                 return true;