Refactor getInstalledRelatedApps code and add manifest logic and tests.

content/renderer/installedapp/related_apps_fetcher.h

+// 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.
+
+#ifndef CONTENT_RENDERER_INSTALLEDAPP_RELATED_APPS_FETCHER_H
+#define CONTENT_RENDERER_INSTALLEDAPP_RELATED_APPS_FETCHER_H
+
+#include <string>
+
+#include "base/compiler_specific.h"
+#include "content/common/content_export.h"
+#include "third_party/WebKit/public/platform/modules/installedapp/WebRelatedAppsFetcher.h"
+
+namespace content {
+
+struct Manifest;
+struct ManifestDebugInfo;
+class ManifestManager;
+
+class CONTENT_EXPORT RelatedAppsFetcher
+    : public NON_EXPORTED_BASE(blink::WebRelatedAppsFetcher) {
+ public:
+  explicit RelatedAppsFetcher(ManifestManager* manifest_manager);
+  ~RelatedAppsFetcher() override;
+
+  // blink::WebRelatedAppsFetcher overrides:
+  void getManifestRelatedApplications(
+      std::unique_ptr<blink::WebCallbacks<
+          const blink::WebVector<blink::WebRelatedApplication>&,
+          void>> callbacks) override;
+
+ private:
+  // Callback for when the manifest has been fetched, triggered by a call to
+  // getManifestRelatedApplications.
+  void OnGetManifestForRelatedApplications(
+      std::unique_ptr<blink::WebCallbacks<
+          const blink::WebVector<blink::WebRelatedApplication>&,
+          void>> callbacks,
+      const GURL& url,
+      const Manifest& manifest,
+      const ManifestDebugInfo& manifest_debug_info);
+
+  ManifestManager* manifest_manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(RelatedAppsFetcher);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_INSTALLEDAPP_RELATED_APPS_FETCHER_H