Reenable assertion after issue was fixed.

src/spaces.cc

Index: src/spaces.cc
diff --git a/src/spaces.cc b/src/spaces.cc
index 9ae2e625d042076a279512f7b3223d2b884df1e3..c0a907338ec68f7cd9074654e3e0eeadfc4b2093 100644
--- a/src/spaces.cc
+++ b/src/spaces.cc
@@ -815,7 +815,7 @@ void PagedSpace::Verify(ObjectVisitor* visitor) {
       ASSERT(object->address() + size <= top);
       end_of_previous_object = object->address() + size;
     }
-    // TODO(1672): Assert that black_size <= page->LiveBytes().
+    ASSERT(black_size <= page->LiveBytes());
   }
   ASSERT(allocation_pointer_found_in_space);
 }