AK: Add to_string() method to StringView

This allows easy creation of a new string from an existing StringView.
Can be used e.g. for output with printf(..., view.to_string().characters())
instead of writing printf(..., String{view}.characters()).

AK/StringView.cpp

@@ -264,4 +264,6 @@ Optional<size_t> StringView::find_last_of(const StringView& view) const
     return {};
 }
 
+String StringView::to_string() const { return String { *this }; }
+
 }