Use completedRenderEndTime as the start of the commit phase if it's an immediate commit (#31527)

We don't log a phase like "Throttled" or "Suspended" for this case so it
can leave a tiny gap otherwise.

This ensures it connects without a seam.

<img width="1059" alt="Screenshot 2024-11-12 at 9 34 17 PM"
src="https://github.com/user-attachments/assets/7ed4a3c7-b508-4fc1-b956-44c4e31faa4d">

Author: sebmarkbage

packages/react-reconciler/src/ReactFiberWorkLoop.js

@@ -3250,7 +3250,12 @@ function commitRootImpl(
 
   if (enableProfilerTimer && enableComponentPerformanceTrack) {
     recordCommitEndTime();
-    logCommitPhase(commitStartTime, commitEndTime);
+    logCommitPhase(
+      suspendedCommitReason === IMMEDIATE_COMMIT
+        ? completedRenderEndTime
+        : commitStartTime,
+      commitEndTime,
+    );
   }
 
   const rootDidHavePassiveEffects = rootDoesHavePassiveEffects;