Convert //sync from scoped_ptr to std::unique_ptr

sync/engine/commit.h

Index: sync/engine/commit.h
diff --git a/sync/engine/commit.h b/sync/engine/commit.h
index 476aa924f7e9ac65d609e4e0433bb35a67eff494..1a8c44e329f3026e4e39465da08822fb50801242 100644
--- a/sync/engine/commit.h
+++ b/sync/engine/commit.h
@@ -8,10 +8,10 @@
 #include <stddef.h>
 
 #include <map>
+#include <memory>
 #include <string>
 
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "sync/base/sync_export.h"
 #include "sync/engine/commit_contribution.h"
 #include "sync/internal_api/public/base/model_type.h"
@@ -41,7 +41,8 @@ class Syncer;
 // PostAndProcessCommitResponse() functions.  So they ended up here.
 class SYNC_EXPORT Commit {
  public:
-  typedef std::map<ModelType, scoped_ptr<CommitContribution>> ContributionMap;
+  typedef std::map<ModelType, std::unique_ptr<CommitContribution>>
+      ContributionMap;
 
   Commit(ContributionMap contributions,
          const sync_pb::ClientToServerMessage& message,