Add flag to trace object groups

src/heap/incremental-marking.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_INCREMENTAL_MARKING_H_
 #define V8_HEAP_INCREMENTAL_MARKING_H_
 
 #include "src/cancelable-task.h"
 #include "src/execution.h"
 #include "src/heap/heap.h"
@@ skipping 87 matching lines @@
 
   void Stop();
 
   void FinalizeMarking(CompletionAction action);
 
   void MarkingComplete(CompletionAction action);
 
   void Epilogue();
 
   // Performs incremental marking steps of step_size_in_bytes as long as
-  // deadline_ins_ms is not reached. step_size_in_bytes can be 0 to compute
+  // deadline_in_ms is not reached. step_size_in_bytes can be 0 to compute
   // an estimate increment. Returns the remaining time that cannot be used
   // for incremental marking anymore because a single step would exceed the
   // deadline.
   double AdvanceIncrementalMarking(intptr_t step_size_in_bytes,
                                    double deadline_in_ms,
                                    StepActions step_actions);
 
   // It's hard to know how much work the incremental marker should do to make
   // progress in the face of the mutator creating new work for it.  We start
   // of at a moderate rate of work and gradually increase the speed of the
@@ skipping 180 matching lines @@
   GCRequestType request_type_;
 
   IncrementalMarkingJob incremental_marking_job_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(IncrementalMarking);
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_INCREMENTAL_MARKING_H_