Lift dynamic prop merging to ConcreteComponentDescriptor (react#48939)

Summary:

The `enableAccumulatedUpdatesInRawPropsAndroid` experiment needs additional context for finer setup. Specifically it needs to be conditionally enabled based on a component name. This information is not accessible form the `Props` constructor.

This diff moves the experimental logic to `ConcreteComponentDescriptor`.

Changelog: [Internal]

Differential Revision: D68633985

Author: Dmitry Rykun

packages/react-native/ReactCommon/react/renderer/core/ConcreteComponentDescriptor.h

@@ -13,6 +13,7 @@
 #include <react/debug/react_native_assert.h>
 #include <react/featureflags/ReactNativeFeatureFlags.h>
 #include <react/renderer/core/ComponentDescriptor.h>
+#include <react/renderer/core/DynamicPropsUtilities.h>
 #include <react/renderer/core/EventDispatcher.h>
 #include <react/renderer/core/Props.h>
 #include <react/renderer/core/PropsParserContext.h>
@@ -114,16 +115,23 @@ class ConcreteComponentDescriptor : public ComponentDescriptor {
 
     rawProps.parse(rawPropsParser_);
 
-    auto shadowNodeProps = ShadowNodeT::Props(context, rawProps, props);
+    std::optional<RawProps> mergedRawProps = std::nullopt;
+#ifdef ANDROID
+    if (ReactNativeFeatureFlags::enableAccumulatedUpdatesInRawPropsAndroid()) {
+      mergedRawProps.emplace(RawProps{mergeDynamicProps(
+          props->rawProps, rawProps.toDynamic(), NullValueStrategy::Override)});
+    }
+#endif
+    auto shadowNodeProps = ShadowNodeT::Props(
+        context,
+        mergedRawProps.has_value() ? *mergedRawProps : rawProps,
+        props);
+
     // Use the new-style iterator
     // Note that we just check if `Props` has this flag set, no matter
     // the type of ShadowNode; it acts as the single global flag.
     if (ReactNativeFeatureFlags::enableCppPropsIteratorSetter()) {
-#ifdef ANDROID
-      const auto& dynamic = shadowNodeProps->rawProps;
-#else
-      const auto& dynamic = static_cast<folly::dynamic>(rawProps);
-#endif
+      const auto& dynamic = rawProps.toDynamic();
       for (const auto& pair : dynamic.items()) {
         const auto& name = pair.first.getString();
         shadowNodeProps->setProp(

packages/react-native/ReactCommon/react/renderer/core/Props.cpp

@@ -10,7 +10,6 @@
 #include <react/renderer/core/propsConversions.h>
 
 #include <react/featureflags/ReactNativeFeatureFlags.h>
-#include "DynamicPropsUtilities.h"
 
 namespace facebook::react {
 
@@ -32,15 +31,7 @@ void Props::initialize(
       ? sourceProps.nativeId
       : convertRawProp(context, rawProps, "nativeID", sourceProps.nativeId, {});
 #ifdef ANDROID
-  if (ReactNativeFeatureFlags::enableAccumulatedUpdatesInRawPropsAndroid()) {
-    auto& oldRawProps = sourceProps.rawProps;
-    auto newRawProps = rawProps.toDynamic(filterObjectKeys);
-    auto mergedRawProps = mergeDynamicProps(
-        oldRawProps, newRawProps, NullValueStrategy::Override);
-    this->rawProps = mergedRawProps;
-  } else {
-    this->rawProps = rawProps.toDynamic(filterObjectKeys);
-  }
+  this->rawProps = rawProps.toDynamic(filterObjectKeys);
 #endif
 }