[heap] Bound number of tasks by embedder limit instead of artificially capping

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 7303f071881abc3d36a1f75abfe677862c22fd6d..424c5d54217ad857fc0333c43735f34687f91562 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -327,6 +327,13 @@ class MarkCompactCollectorBase {
   // Returns whether this page should be moved according to heuristics.
   bool ShouldMovePage(Page* p, intptr_t live_bytes);
 
+  template <RememberedSetType type>
+  void UpdatePointersInParallel(Heap* heap, base::Semaphore* semaphore,
+                                const MarkCompactCollectorBase* collector);
+
+  int NumberOfParallelCompactionTasks(int pages);
+  int NumberOfPointerUpdateTasks(int pages);
+
   Heap* heap_;
 };