Convert //chrome from scoped_ptr to std::unique_ptr

chrome/utility/image_writer/image_writer.h

Index: chrome/utility/image_writer/image_writer.h
diff --git a/chrome/utility/image_writer/image_writer.h b/chrome/utility/image_writer/image_writer.h
index ad7b0bc8c0fef78948b24de41df9291aad1ad9f2..7129bdda801fb48ca1fd9a09ac9687e83e1edd48 100644
--- a/chrome/utility/image_writer/image_writer.h
+++ b/chrome/utility/image_writer/image_writer.h
@@ -7,13 +7,13 @@
 
 #include <stdint.h>
 
+#include <memory>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "build/build_config.h"
 
@@ -88,7 +88,7 @@ class ImageWriter : public base::SupportsWeakPtr<ImageWriter> {
 
 #if defined(OS_MACOSX)
   friend class DiskUnmounterMac;
-  scoped_ptr<DiskUnmounterMac> unmounter_;
+  std::unique_ptr<DiskUnmounterMac> unmounter_;
 #endif
 
   ImageWriterHandler* handler_;