Implement BackgroundFetchManager.fetch() and struct traits

content/common/background_fetch/background_fetch_struct_traits.cc

+// Copyright 2017 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 "content/common/background_fetch/background_fetch_struct_traits.h"
+
+#include "mojo/public/cpp/bindings/array_data_view.h"
+
+namespace mojo {
+
+// static
+bool StructTraits<blink::mojom::BackgroundFetchOptionsDataView,
+                  content::BackgroundFetchOptions>::
+    Read(blink::mojom::BackgroundFetchOptionsDataView data,
+         content::BackgroundFetchOptions* options) {
+  if (!data.ReadIcons(&options->icons) || !data.ReadTitle(&options->title))
+    return false;
+
+  options->total_download_size = data.total_download_size();
+  return true;
+}
+
+// static
+bool StructTraits<blink::mojom::BackgroundFetchRegistrationDataView,
+                  content::BackgroundFetchRegistration>::
+    Read(blink::mojom::BackgroundFetchRegistrationDataView data,
+         content::BackgroundFetchRegistration* registration) {
+  if (!data.ReadTag(&registration->tag) ||
+      !data.ReadIcons(&registration->icons) ||
+      !data.ReadTitle(&registration->title)) {
+    return false;
+  }
+
+  registration->total_download_size = data.total_download_size();
+  return true;
+}
+
+// static
+bool StructTraits<
+    blink::mojom::IconDefinitionDataView,
+    content::IconDefinition>::Read(blink::mojom::IconDefinitionDataView data,
+                                   content::IconDefinition* definition) {
+  return data.ReadSrc(&definition->src) && data.ReadSizes(&definition->sizes) &&
+         data.ReadType(&definition->type);
+}
+
+}  // namespace mojo