Force scavenge in idle notification if we estimate that it will take long.

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 8c103dd23d42d6eced6f9c2c668329c9899a43ae..0fdbb69ebd2ecec407abce31b697e21daf09f47f 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -4311,7 +4311,7 @@ bool Heap::IdleNotification(int idle_time_in_ms) {
       tracer()->IncrementalMarkingSpeedInBytesPerMillisecond());
   heap_state.scavenge_speed_in_bytes_per_ms =
       static_cast<size_t>(tracer()->ScavengeSpeedInBytesPerMillisecond());
-  heap_state.available_new_space_memory = new_space_.Available();
+  heap_state.used_new_space_size = new_space_.Size();
   heap_state.new_space_capacity = new_space_.Capacity();
   heap_state.new_space_allocation_throughput_in_bytes_per_ms =
       static_cast<size_t>(