Merge r10809 from the bleeding_edge to the 3.8 branch.

src/spaces-inl.h

Index: src/spaces-inl.h
===================================================================
--- src/spaces-inl.h	(revision 10877)
+++ src/spaces-inl.h	(working copy)
@@ -166,10 +166,8 @@
   Page* page = reinterpret_cast<Page*>(chunk);
   ASSERT(chunk->size() == static_cast<size_t>(kPageSize));
   ASSERT(chunk->owner() == owner);
-  owner->IncreaseCapacity(Page::kObjectAreaSize);
-  owner->Free(page->ObjectAreaStart(),
-              static_cast<int>(page->ObjectAreaEnd() -
-                               page->ObjectAreaStart()));
+  owner->IncreaseCapacity(page->area_size());
+  owner->Free(page->area_start(), page->area_size());
 
   heap->incremental_marking()->SetOldSpacePageFlags(chunk);