Fix freeform window can't resize after maximize window and restore

The freeform window mode would change to fullscreen if it maximzed
window size, that could set the touch region crop to its stack bounds.
And we should clear that after it restore to freeform window mode.

Bug: 152248369
Test: enter freeform window mode, open an app and maximize it,
      restore and resize it.
Change-Id: I7249a682ca3ed0f4ce89fc05413c8d24c8dc83de

services/core/java/com/android/server/wm/WindowState.java

@@ -3346,6 +3346,7 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
 
         final ActivityStack stack = task.getStack();
         if (stack == null || inFreeformWindowingMode()) {
+            handle.setTouchableRegionCrop(null);
             return;
         }