Fabric: MountingTelemetry and refinments in TimeUtils

Summary: This diff implements encapsulating all time metrics in a single class for better extensibility and readability.

Reviewed By: JoshuaGross

Differential Revision: D15179835

fbshipit-source-id: 62bdf94435a0d37a87ad9bad613cc8e38043a235

ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp

@@ -503,8 +503,8 @@ void Binding::schedulerDidFinishTransaction(
   scheduleMountItems(
       javaUIManager_,
       batch.get(),
-      telemetry.commitStartTime,
-      telemetry.layoutTime,
+      telemetry.getCommitStartTime(),
+      telemetry.getLayoutTime(),
       finishTransactionStartTime,
       finishTransactionEndTime);
 }