Mojo C++ bindings: switch the existing usage of StructTraits to use the new data view interface.

mojo/public/cpp/bindings/lib/array_traits_standard.h

Index: mojo/public/cpp/bindings/lib/array_traits_standard.h
diff --git a/mojo/public/cpp/bindings/lib/array_traits_standard.h b/mojo/public/cpp/bindings/lib/array_traits_standard.h
index a17a3f9095cb3104b3a1ab88930233065ffcd437..09bdbb0a5d5303f1716399a912cf1bf3b602ed08 100644
--- a/mojo/public/cpp/bindings/lib/array_traits_standard.h
+++ b/mojo/public/cpp/bindings/lib/array_traits_standard.h
@@ -15,6 +15,7 @@ struct ArrayTraits<Array<T>> {
   using Element = T;
 
   static bool IsNull(const Array<T>& input) { return input.is_null(); }
+  static void SetToNull(Array<T>* output) { *output = nullptr; }
 
   static size_t GetSize(const Array<T>& input) { return input.size(); }
 
@@ -32,8 +33,6 @@ struct ArrayTraits<Array<T>> {
   }
 
   static void Resize(Array<T>& input, size_t size) { input.resize(size); }
-
-  static void SetToNull(Array<T>& input) { input = nullptr; }
 };
 
 }  // namespace mojo