Convert //ios from scoped_ptr to std::unique_ptr.

ios/web/navigation/navigation_item_impl.h

Index: ios/web/navigation/navigation_item_impl.h
diff --git a/ios/web/navigation/navigation_item_impl.h b/ios/web/navigation/navigation_item_impl.h
index 8462cbd671b0a4c0f33c2f198df10481e696a008..882b62dc514339375b08a4303e99ee7fdf1a2a26 100644
--- a/ios/web/navigation/navigation_item_impl.h
+++ b/ios/web/navigation/navigation_item_impl.h
@@ -7,8 +7,9 @@
 
 #import <Foundation/Foundation.h>
 
+#include <memory>
+
 #include "base/mac/scoped_nsobject.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 #include "ios/web/navigation/navigation_item_facade_delegate.h"
 #include "ios/web/public/favicon_status.h"
@@ -36,7 +37,7 @@ class NavigationItemImpl : public web::NavigationItem {
   // NOTE: to minimize facade synchronization code, NavigationItems take
   // ownership of their facade delegates.
   void SetFacadeDelegate(
-      scoped_ptr<NavigationItemFacadeDelegate> facade_delegate);
+      std::unique_ptr<NavigationItemFacadeDelegate> facade_delegate);
   NavigationItemFacadeDelegate* GetFacadeDelegate() const;
 
   // NavigationItem implementation:
@@ -138,7 +139,7 @@ class NavigationItemImpl : public web::NavigationItem {
   mutable base::string16 cached_display_title_;
 
   // Weak pointer to the facade delegate.
-  scoped_ptr<NavigationItemFacadeDelegate> facade_delegate_;
+  std::unique_ptr<NavigationItemFacadeDelegate> facade_delegate_;
 
   // Copy and assignment is explicitly allowed for this class.
 };