[Media Router] Clean up issues related code.

chrome/browser/media/router/mojo/media_router_struct_traits.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/media/router/mojo/media_router_struct_traits.h"
+
+namespace mojo {
+
+// static
+bool StructTraits<media_router::mojom::IssueDataView, media_router::IssueInfo>::
+    Read(media_router::mojom::IssueDataView data,
+         media_router::IssueInfo* out) {
+  if (!data.ReadTitle(&out->title))
+    return false;
+
+  if (!data.ReadDefaultAction(&out->default_action))
+    return false;
+
+  if (!data.ReadSeverity(&out->severity))
+    return false;
+
+  base::Optional<std::string> message;
+  if (!data.ReadMessage(&message))
+    return false;
+
+  out->message = message.value_or(std::string());
+
+  if (!data.ReadSecondaryActions(&out->secondary_actions))
+    return false;
+
+  base::Optional<std::string> route_id;
+  if (!data.ReadRouteId(&route_id))
+    return false;
+
+  out->route_id = route_id.value_or(std::string());
+
+  out->is_blocking = data.is_blocking();
+  out->help_page_id = data.help_page_id();
+
+  return true;
+}
+
+}  // namespace mojo