Local NTP: Deploy strict-dynamic CSP

chrome/browser/search/google_search_provider_service.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 CHROME_BROWSER_SEARCH_GOOGLE_SEARCH_PROVIDER_SERVICE_H_
+#define CHROME_BROWSER_SEARCH_GOOGLE_SEARCH_PROVIDER_SERVICE_H_
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "base/scoped_observer.h"
+#include "chrome/browser/search/google_search_provider_service_observer.h"
+#include "components/keyed_service/core/keyed_service.h"
+#include "components/search_engines/template_url_service_observer.h"
+
+class TemplateURLService;
+
+// Tracks whether the default search provider is Google.

[sfiera, 2017/04/11 09:45:17]

Comments? Tests? It's not clear from the header why this class exists, what you
gain by using it over observing TemplateURLService directly, or if it delivers
on it.

[Marc Treib, 2017/04/11 12:37:59]

Two things:
1) It abstracts away the kinda yucky TemplateURL wrangling. I think this should
be clear from the new comments.
2) It notifies observers when it's shutting down, so they can de-register. I've
added a comment to Add/RemoveObserver. (Of course, this functionality could be
added to TemplateURLService too.)

[sfiera, 2017/04/11 14:07:35]

On its own, I'm not sure that motivates this class to exist. Exposing
DefaultSearchProviderIsGoogleImpl() would serve as well, or better.
Can we add a TODO or a bug to add shutdown to its observer interface?

[Marc Treib, 2017/04/12 11:53:45]

You're right, this isn't really worth a new service. I've added an OnShutdown
method to TemplateURLServiceObserver (in a separate CL) and removed the new
service again. Let's see what the TemplateURLService owners say.

+class GoogleSearchProviderService : public KeyedService,
+                                    public TemplateURLServiceObserver {
+ public:
+  explicit GoogleSearchProviderService(
+      TemplateURLService* template_url_service);
+  ~GoogleSearchProviderService() override;
+
+  // KeyedService implementation.
+  void Shutdown() override;
+
+  bool DefaultSearchProviderIsGoogle() const;
+
+  void AddObserver(GoogleSearchProviderServiceObserver* observer);
+  void RemoveObserver(GoogleSearchProviderServiceObserver* observer);
+
+ private:
+  // TemplateURLServiceObserver implementation.
+  void OnTemplateURLServiceChanged() override;
+
+  TemplateURLService* template_url_service_;
+  ScopedObserver<TemplateURLService, GoogleSearchProviderService>
+      template_url_service_observer_;
+
+  bool is_google_;
+
+  base::ObserverList<GoogleSearchProviderServiceObserver, true> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(GoogleSearchProviderService);
+};
+
+#endif  // CHROME_BROWSER_SEARCH_GOOGLE_SEARCH_PROVIDER_SERVICE_H_