Change halfway-to-the-max GC trigger to measure committed pages, not allocated objects

src/heap/heap-inl.h

Index: src/heap/heap-inl.h
diff --git a/src/heap/heap-inl.h b/src/heap/heap-inl.h
index f2c593e7f87da03fe1bad50cf6fcf65c796f769a..f893b75216262c734b866ff663189c330baa4b26 100644
--- a/src/heap/heap-inl.h
+++ b/src/heap/heap-inl.h
@@ -349,7 +349,9 @@ bool Heap::InOldDataSpace(Object* object) {
 
 bool Heap::OldGenerationAllocationLimitReached() {
   if (!incremental_marking()->IsStopped()) return false;
-  return OldGenerationSpaceAvailable() < 0;
+  return OldGenerationSpaceAvailable() < 0 ||
+         old_generation_committed_memory_limit_ <
+             CommittedOldGenerationMemory();
 }