Refactor large object sweeping.

Moved basic sweeping logic into large_object_space.cc.
Renamed SpaceSetMap -> ObjectSet.

Change-Id: I938c1f29f69b0682350347da2bd5de021c0e0224
diff --git a/runtime/gc/collector/mark_sweep.cc b/runtime/gc/collector/mark_sweep.cc
index 937ff6d..5d450a7 100644
--- a/runtime/gc/collector/mark_sweep.cc
+++ b/runtime/gc/collector/mark_sweep.cc
@@ -465,7 +465,7 @@
 bool MarkSweep::MarkLargeObject(const Object* obj, bool set) {
   // TODO: support >1 discontinuous space.
   space::LargeObjectSpace* large_object_space = GetHeap()->GetLargeObjectsSpace();
-  accounting::SpaceSetMap* large_objects = large_object_space->GetMarkObjects();
+  accounting::ObjectSet* large_objects = large_object_space->GetMarkObjects();
   if (kProfileLargeObjects) {
     ++large_object_test_;
   }
@@ -1112,8 +1112,8 @@
   }
   // Handle the large object space.
   space::LargeObjectSpace* large_object_space = GetHeap()->GetLargeObjectsSpace();
-  accounting::SpaceSetMap* large_live_objects = large_object_space->GetLiveObjects();
-  accounting::SpaceSetMap* large_mark_objects = large_object_space->GetMarkObjects();
+  accounting::ObjectSet* large_live_objects = large_object_space->GetLiveObjects();
+  accounting::ObjectSet* large_mark_objects = large_object_space->GetMarkObjects();
   if (swap_bitmaps) {
     std::swap(large_live_objects, large_mark_objects);
   }
@@ -1163,23 +1163,9 @@
 
 void MarkSweep::SweepLargeObjects(bool swap_bitmaps) {
   TimingLogger::ScopedSplit("SweepLargeObjects", &timings_);
-  // Sweep large objects
-  space::LargeObjectSpace* large_object_space = GetHeap()->GetLargeObjectsSpace();
-  accounting::SpaceSetMap* large_live_objects = large_object_space->GetLiveObjects();
-  accounting::SpaceSetMap* large_mark_objects = large_object_space->GetMarkObjects();
-  if (swap_bitmaps) {
-    std::swap(large_live_objects, large_mark_objects);
-  }
-  // O(n*log(n)) but hopefully there are not too many large objects.
   size_t freed_objects = 0;
   size_t freed_bytes = 0;
-  Thread* self = Thread::Current();
-  for (const Object* obj : large_live_objects->GetObjects()) {
-    if (!large_mark_objects->Test(obj)) {
-      freed_bytes += large_object_space->Free(self, const_cast<Object*>(obj));
-      ++freed_objects;
-    }
-  }
+  GetHeap()->GetLargeObjectsSpace()->Sweep(swap_bitmaps, &freed_objects, &freed_bytes);
   freed_large_objects_.FetchAndAdd(freed_objects);
   freed_large_object_bytes_.FetchAndAdd(freed_bytes);
   GetHeap()->RecordFree(freed_objects, freed_bytes);