[heap] Remove TryFinalizeIdleIncrementalMarking.

src/heap/heap.h

Index: src/heap/heap.h
diff --git a/src/heap/heap.h b/src/heap/heap.h
index 13c832ec28b51b85a46dd784c40e8587f2faa5b4..e4e093ce229bd23b830173d07665542d63d4eb4d 100644
--- a/src/heap/heap.h
+++ b/src/heap/heap.h
@@ -1257,9 +1257,6 @@ class Heap {
 
   void FinalizeIncrementalMarkingIfComplete(GarbageCollectionReason gc_reason);
 
-  bool TryFinalizeIdleIncrementalMarking(double idle_time_in_ms,
-                                         GarbageCollectionReason gc_reason);
-
   void RegisterReservationsForBlackAllocation(Reservation* reservations);
 
   IncrementalMarking* incremental_marking() { return incremental_marking_; }