Convert //sync from scoped_ptr to std::unique_ptr

sync/syncable/directory.cc

Index: sync/syncable/directory.cc
diff --git a/sync/syncable/directory.cc b/sync/syncable/directory.cc
index 207b8d55a334248884f14191dbd24a390c3659cc..b6d314364fd0f3bb11a6e48557dfda6853d8cf7c 100644
--- a/sync/syncable/directory.cc
+++ b/sync/syncable/directory.cc
@@ -1134,10 +1134,10 @@ void Directory::CollectMetaHandleCounts(
   }
 }
 
-scoped_ptr<base::ListValue> Directory::GetNodeDetailsForType(
+std::unique_ptr<base::ListValue> Directory::GetNodeDetailsForType(
     BaseTransaction* trans,
     ModelType type) {
-  scoped_ptr<base::ListValue> nodes(new base::ListValue());
+  std::unique_ptr<base::ListValue> nodes(new base::ListValue());
 
   ScopedKernelLock lock(this);
   for (MetahandlesMap::iterator it = kernel_->metahandles_map.begin();
@@ -1147,7 +1147,7 @@ scoped_ptr<base::ListValue> Directory::GetNodeDetailsForType(
     }
 
     EntryKernel* kernel = it->second;
-    scoped_ptr<base::DictionaryValue> node(
+    std::unique_ptr<base::DictionaryValue> node(
         kernel->ToValue(GetCryptographer(trans)));
 
     // Add the position index if appropriate.  This must be done here (and not