Add backgroundImage prop diffing to View (facebook#54042)

Summary:
Pull Request resolved: facebook#54042

Update the View component props to diff the `backgroundImage` property and assign the value to `experimental_backgroundImage` which maps to the `backgroundImage` property on the Android `ReactViewManager`.

Changelog: [Internal]

Reviewed By: christophpurrer

Differential Revision: D83788008

fbshipit-source-id: 5f9d93403af483c9494d2782aedad604cbb7cbbc

Author: Nick Lefever

packages/react-native/ReactCommon/react/renderer/components/view/platform/android/react/renderer/components/view/HostPlatformViewProps.cpp

@@ -663,6 +663,10 @@ folly::dynamic HostPlatformViewProps::getDiffProps(
     result["filter"] = toDynamic(filter);
   }
 
+  if (backgroundImage != oldProps->backgroundImage) {
+    result["experimental_backgroundImage"] = toDynamic(backgroundImage);
+  }
+
   if (mixBlendMode != oldProps->mixBlendMode) {
     result["mixBlendMode"] = toString(mixBlendMode);
   }

packages/react-native/ReactCommon/react/renderer/graphics/BackgroundImage.h

@@ -16,4 +16,15 @@ namespace facebook::react {
 
 using BackgroundImage = std::variant<LinearGradient, RadialGradient>;
 
+#ifdef RN_SERIALIZABLE_STATE
+inline folly::dynamic toDynamic(const BackgroundImage& backgroundImage) {
+  if (std::holds_alternative<LinearGradient>(backgroundImage)) {
+    return std::get<LinearGradient>(backgroundImage).toDynamic();
+  } else if (std::holds_alternative<RadialGradient>(backgroundImage)) {
+    return std::get<RadialGradient>(backgroundImage).toDynamic();
+  }
+  return folly::dynamic(nullptr);
+}
+#endif
+
 }; // namespace facebook::react