Manage size of lists used in global handles

src/global-handles.cc

Index: src/global-handles.cc
diff --git a/src/global-handles.cc b/src/global-handles.cc
index 6a6b6ef8603b23e47654f9bc531191d2cb649f82..8e0ff13d3341e8ab6bb9befdbd481186312e2159 100644
--- a/src/global-handles.cc
+++ b/src/global-handles.cc
@@ -786,6 +786,7 @@ void GlobalHandles::UpdateListOfNewSpaceNodes() {
     }
   }
   new_space_nodes_.Rewind(last);
+  new_space_nodes_.Trim();
 }
 
 
@@ -811,6 +812,7 @@ int GlobalHandles::DispatchPendingPhantomCallbacks() {
     // Fire second pass callback.
     callback.Invoke(isolate());
   }
+  pending_phantom_callbacks_.Clear();
   return freed_nodes;
 }