Do not flatten views with PointerEvents props

Summary:
Some of the values of pointer events should be propagated across the hierarchy of views, e.g. the pointerEvent value NONE: https://reactnative.dev/docs/view#pointerevents
That mean that we can't flatten these views (or we should propagate these values across alll the hierarchy of a view that is being flatten)
For now I'm going to prevent these views to be flatten, this behavior is consistent with the Adroid view flattening algorithm:
https://our.intern.facebook.com/intern/diffusion/FBS/browse/master/xplat/js/react-native-github/ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewProps.java?commit=1144adb5b45bf9a8c8cedf4ac86a2e9ccb429815&lines=249

changelog: [internal]

Reviewed By: shergin

Differential Revision: D20180804

fbshipit-source-id: 1fe7fc99c873a28c077b3859f8a7884d38b6d4d8

Author: mdvacca

ReactCommon/fabric/components/view/ViewShadowNode.cpp

@@ -6,6 +6,7 @@
  */
 
 #include "ViewShadowNode.h"
+#include <react/components/view/primitives.h>
 
 namespace facebook {
 namespace react {
@@ -20,6 +21,8 @@ bool ViewShadowNode::isLayoutOnly() const {
       viewProps.nativeId.empty() &&
       // Accessibility Props
       !viewProps.accessible &&
+      // Pointer events Props
+      (viewProps.pointerEvents == PointerEventsMode::Auto || viewProps.pointerEvents == PointerEventsMode::BoxNone) &&
       // Style Props
       viewProps.opacity == 1.0 && !viewProps.backgroundColor &&
       !viewProps.foregroundColor && !viewProps.shadowColor &&