[heap] No leakage of incremental-marking.h outside of heap.

src/heap/incremental-marking.h

Index: src/heap/incremental-marking.h
diff --git a/src/heap/incremental-marking.h b/src/heap/incremental-marking.h
index fb6e5cf6ab47be099da81231d24fe519c2b012de..010392875e6ab2d292927b6b1d434146f1bba7b2 100644
--- a/src/heap/incremental-marking.h
+++ b/src/heap/incremental-marking.h
@@ -103,6 +103,15 @@ class IncrementalMarking {
 
   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
+  // 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