[heap] Remove deadcode for retrieving last idle notification

Bug: v8:12968
Change-Id: I87d2ec47a250e4f69cf5c7002c254bd50276004b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3702800Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81137}

src/heap/heap.cc

@@ -4108,10 +4108,9 @@ bool Heap::PerformIdleTimeAction(GCIdleTimeAction action,
 void Heap::IdleNotificationEpilogue(GCIdleTimeAction action,
                                     GCIdleTimeHeapState heap_state,
                                     double start_ms, double deadline_in_ms) {
-  double idle_time_in_ms = deadline_in_ms - start_ms;
-  double current_time = MonotonicallyIncreasingTimeInMs();
-  last_idle_notification_time_ = current_time;
-  double deadline_difference = deadline_in_ms - current_time;
+  const double idle_time_in_ms = deadline_in_ms - start_ms;
+  const double deadline_difference =
+      deadline_in_ms - MonotonicallyIncreasingTimeInMs();
 
   if (FLAG_trace_idle_notification) {
     isolate_->PrintWithTimestamp(
@@ -4179,12 +4178,6 @@ bool Heap::IdleNotification(double deadline_in_seconds) {
   return result;
 }
 
-bool Heap::RecentIdleNotificationHappened() {
-  return (last_idle_notification_time_ +
-          GCIdleTimeHandler::kMaxScheduledIdleTime) >
-         MonotonicallyIncreasingTimeInMs();
-}
-
 class MemoryPressureInterruptTask : public CancelableTask {
  public:
   explicit MemoryPressureInterruptTask(Heap* heap)

src/heap/heap.h

@@ -2059,12 +2059,6 @@ class Heap {
 
   void RecomputeLimits(GarbageCollector collector);
 
-  // ===========================================================================
-  // Idle notification. ========================================================
-  // ===========================================================================
-
-  bool RecentIdleNotificationHappened();
-
   // ===========================================================================
   // GC Tasks. =================================================================
   // ===========================================================================
@@ -2322,9 +2316,6 @@ class Heap {
   // Total time spent in GC.
   double total_gc_time_ms_ = 0.0;
 
-  // Last time an idle notification happened.
-  double last_idle_notification_time_ = 0.0;
-
   // Last time a garbage collection happened.
   double last_gc_time_ = 0.0;