Rate limit programmatic update checks for extensions

extensions/browser/updater/extension_downloader_test_delegate.h

+// 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.
+
+#ifndef EXTENSIONS_BROWSER_UPDATER_EXTENSION_DOWNLOADER_TEST_DELEGATE_H_
+#define EXTENSIONS_BROWSER_UPDATER_EXTENSION_DOWNLOADER_TEST_DELEGATE_H_
+
+#include <memory>
+
+namespace extensions {
+
+class ExtensionDownloader;
+class ExtensionDownloaderDelegate;
+class ManifestFetchData;
+
+// A class for intercepting the work of checking for / downloading extension
+// updates.
+class ExtensionDownloaderTestDelegate {
+ public:
+  // This method gets called when an update check is being started for an
+  // extension. Normally implementors should eventually call either
+  // OnExtensionDownloadFailed or OnExtensionDownloadFinished on
+  // |delegate|.
+  virtual void StartUpdateCheck(
+      ExtensionDownloader* downloader,
+      ExtensionDownloaderDelegate* delegate,
+      std::unique_ptr<ManifestFetchData> fetch_data) = 0;
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_UPDATER_EXTENSION_DOWNLOADER_TEST_DELEGATE_H_