Local NTP: Introduce OneGoogleBarFetcher

chrome/browser/search/one_google_bar/one_google_bar_fetcher.h

Index: chrome/browser/search/one_google_bar/one_google_bar_fetcher.h
diff --git a/chrome/browser/search/one_google_bar/one_google_bar_fetcher.h b/chrome/browser/search/one_google_bar/one_google_bar_fetcher.h
new file mode 100644
index 0000000000000000000000000000000000000000..e74636219388d209f52bd1af4d9f49e9629120f3
--- /dev/null
+++ b/chrome/browser/search/one_google_bar/one_google_bar_fetcher.h
@@ -0,0 +1,21 @@
+// 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_ONE_GOOGLE_BAR_ONE_GOOGLE_BAR_FETCHER_H_
+#define CHROME_BROWSER_SEARCH_ONE_GOOGLE_BAR_ONE_GOOGLE_BAR_FETCHER_H_
+
+#include "base/callback_forward.h"
+#include "base/optional.h"
+
+struct OneGoogleBarData;
+
+class OneGoogleBarFetcher {
+ public:
+  using OneGoogleCallback =
+      base::OnceCallback<void(const base::Optional<OneGoogleBarData>&)>;
+
+  virtual void Fetch(OneGoogleCallback callback) = 0;

[sfiera, 2017/04/12 17:25:47]

Comments?

In particular, I would wonder if the caller, callee, or neither should be
caching the result.

[Marc Treib, 2017/04/13 09:03:34]

Added a comment which hopefully makes things clear - the fetcher just fetches
and doesn't know or care about caching.

+};
+
+#endif  // CHROME_BROWSER_SEARCH_ONE_GOOGLE_BAR_ONE_GOOGLE_BAR_FETCHER_H_