Make AudioParameters a class instead of a struct

content/public/common/common_param_traits.h

Index: content/public/common/common_param_traits.h
diff --git a/content/public/common/common_param_traits.h b/content/public/common/common_param_traits.h
index c768e3db148bda984437a96d8b414b362c5797b6..291896ff41224ae5c45386206ac064196c887724 100644
--- a/content/public/common/common_param_traits.h
+++ b/content/public/common/common_param_traits.h
@@ -21,6 +21,7 @@
 #include "content/public/common/security_style.h"
 #include "googleurl/src/gurl.h"
 #include "ipc/ipc_message_utils.h"
+#include "media/audio/audio_parameters.h"
 #include "net/base/ip_endpoint.h"
 #include "net/url_request/url_request_status.h"
 #include "ui/gfx/native_widget_types.h"
@@ -136,6 +137,14 @@ struct CONTENT_EXPORT ParamTraits<gfx::Rect> {
 };
 
 template <>
+struct CONTENT_EXPORT ParamTraits<AudioParameters> {
+  typedef AudioParameters param_type;
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, void** iter, param_type* r);
+  static void Log(const param_type& p, std::string* l);
+};
+
+template <>
 struct ParamTraits<gfx::NativeWindow> {
   typedef gfx::NativeWindow param_type;
   static void Write(Message* m, const param_type& p) {