Componentize HistoryDatabase

components/history/content/browser/history_database_helper.h

Index: components/history/content/browser/history_database_helper.h
diff --git a/components/history/content/browser/history_database_helper.h b/components/history/content/browser/history_database_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..9da11c1e802e934a6dcca24479ead0e0da191c2e
--- /dev/null
+++ b/components/history/content/browser/history_database_helper.h
@@ -0,0 +1,21 @@
+// Copyright 2015 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 COMPONENTS_HISTORY_CONTENT_BROWSER_HISTORY_DATABASE_HELPER_H_
+#define COMPONENTS_HISTORY_CONTENT_BROWSER_HISTORY_DATABASE_HELPER_H_
+
+namespace base {
+class FilePath;
+}
+
+namespace history {
+
+struct HistoryDatabaseParams;
+
+HistoryDatabaseParams HistoryDatabaseParamsForPath(

[droger, 2015/01/20 09:49:00]

Why is this is a separate file? Could it be another constructor in
HistoryDatabaseParams?

[sdefresne, 2015/01/20 10:28:50]

Because the implementation depends on //content and HistoryDatabaseParams cannot
depends on //content.

+    const base::FilePath& history_dir);
+
+}  // namespace history
+
+#endif  // COMPONENTS_HISTORY_CONTENT_BROWSER_HISTORY_DATABASE_HELPER_H_