Fix Fantom getRenderedOutput not reflecting removed props

Summary:
`RenderOutput::renderView` merged old cached props with new debug props
via `mergeDynamicProps`. Since `getDebugProps()` omits default-valued
props, removed props were never cleared from the cache. Also,
`renderedViews_.insert()` never overwrote existing entries.

Fix by reading debug props directly and using `insert_or_assign`.

Changelog: [Internal]

Differential Revision: D95055704

Author: sammy-SC

packages/react-native/Libraries/Components/View/__tests__/View-itest.js

@@ -670,6 +670,28 @@ describe('<View>', () => {
         );
       });
     });
+
+    describe('nativeID', () => {
+      it('resets nativeID when removed', () => {
+        const root = Fantom.createRoot();
+
+        Fantom.runTask(() => {
+          root.render(<View nativeID="my-id" collapsable={false} />);
+        });
+
+        expect(root.getRenderedOutput({props: ['nativeID']}).toJSX()).toEqual(
+          <rn-view nativeID="my-id" />,
+        );
+
+        Fantom.runTask(() => {
+          root.render(<View collapsable={false} />);
+        });
+
+        expect(root.getRenderedOutput({props: ['nativeID']}).toJSX()).toEqual(
+          <rn-view />,
+        );
+      });
+    });
   });
 
   describe('ref', () => {

private/react-native-fantom/tester/src/render/RenderOutput.cpp

@@ -9,7 +9,6 @@
 #include <react/debug/react_native_assert.h>
 #include <react/renderer/components/text/ParagraphState.h>
 #include <react/renderer/core/ConcreteState.h>
-#include <react/renderer/core/DynamicPropsUtilities.h>
 
 namespace facebook::react {
 
@@ -61,15 +60,7 @@ folly::dynamic RenderOutput::renderView(
   element["type"] = view.componentName;
 
 #if RN_DEBUG_STRING_CONVERTIBLE
-  folly::dynamic props = nullptr;
-  if (auto it = renderedViews_.find(view.tag); it != renderedViews_.end()) {
-    props = mergeDynamicProps(
-        it->second["props"],
-        renderProps(view.props->getDebugProps()),
-        NullValueStrategy::Override);
-  } else {
-    props = renderProps(view.props->getDebugProps());
-  }
+  folly::dynamic props = renderProps(view.props->getDebugProps());
 #else
   folly::dynamic props = folly::dynamic::object;
 #endif
@@ -96,7 +87,7 @@ folly::dynamic RenderOutput::renderView(
 #endif
   element["props"] = props;
 
-  renderedViews_.insert({view.tag, element});
+  renderedViews_.insert_or_assign(view.tag, element);
 
   return element;
 }