[heap] Add VMState to IncrementalMarking observer

src/heap/incremental-marking-job.cc

Index: src/heap/incremental-marking-job.cc
diff --git a/src/heap/incremental-marking-job.cc b/src/heap/incremental-marking-job.cc
index de7264792ac37cd1b6b4c6f99f606300ee18cf61..47a27faf15870b00ac810bb887ff444d0920f915 100644
--- a/src/heap/incremental-marking-job.cc
+++ b/src/heap/incremental-marking-job.cc
@@ -44,7 +44,8 @@ void IncrementalMarkingJob::Task::Step(Heap* heap) {
 
 void IncrementalMarkingJob::Task::RunInternal() {
   VMState<GC> state(isolate());
-  RuntimeCallTimerScope(isolate(), &RuntimeCallStats::GC_IncrementalMarkingJob);
+  RuntimeCallTimerScope runtime_timer(
+      isolate(), &RuntimeCallStats::GC_IncrementalMarkingJob);
 
   Heap* heap = isolate()->heap();
   job_->NotifyTask();