Fabric: Introducing MountingTransaction

Summary:
`MountingTransaction` encapsulates all artifacts of `ShadowTree` commit, particularly list of mutations and meta-data.
We will rely on this heavily in the coming diffs.

Reviewed By: JoshuaGross

Differential Revision: D15021795

fbshipit-source-id: 811da7afd7b929a34a81aa66566193d46bbc34f8

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

@@ -329,11 +329,12 @@ local_ref<JMountItem::javaobject> createDeleteMountItem(
 }
 
 void Binding::schedulerDidFinishTransaction(
-    const Tag rootTag,
-    const ShadowViewMutationList& mutations,
-    const long commitStartTime,
-    const long layoutTime) {
+    MountingTransaction &&mountingTransaction) {
   SystraceSection s("FabricUIManager::schedulerDidFinishTransaction");
+
+  auto telemetry = mountingTransaction.getTelemetry();
+  auto mutations = mountingTransaction.getMutations();
+
   std::vector<local_ref<jobject>> queue;
   // Upper bound estimation of mount items to be delivered to Java side.
   int size = mutations.size() * 3 + 42;
@@ -466,8 +467,8 @@ void Binding::schedulerDidFinishTransaction(
   scheduleMountItems(
       javaUIManager_,
       batch.get(),
-      commitStartTime,
-      layoutTime,
+      telemetry.commitStartTime,
+      telemetry.layoutTime,
       finishTransactionStartTime,
       finishTransactionEndTime);
 }

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

@@ -57,10 +57,7 @@ class Binding : public jni::HybridClass<Binding>, public SchedulerDelegate {
   void stopSurface(jint surfaceId);
 
   void schedulerDidFinishTransaction(
-      const Tag rootTag,
-      const ShadowViewMutationList& mutations,
-      const long commitStartTime,
-      const long layoutTime);
+      MountingTransaction &&mountingTransaction);
 
   void schedulerDidRequestPreliminaryViewAllocation(
       const SurfaceId surfaceId,