Make profile statistics tasks inspectable by tests

chrome/browser/profiles/profile_statistics_constants.h

Index: chrome/browser/profiles/profile_statistics_constants.h
diff --git a/chrome/browser/profiles/profile_statistics_constants.h b/chrome/browser/profiles/profile_statistics_constants.h
new file mode 100644
index 0000000000000000000000000000000000000000..046266f1ce061046ff5239042b958df1a6761265
--- /dev/null
+++ b/chrome/browser/profiles/profile_statistics_constants.h
@@ -0,0 +1,16 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.

[lwchkg, 2016/01/25 21:35:53]

Should I write copyright 2016? (Note that the code is not new. It's moved from
another file.)

[Mike Lerman, 2016/02/01 16:42:01]

When a file's renamed, then keep the original date.
If this is a major refactor and you've made a new class/file (that stole a bunch
of code from another file/class that still exists) then I think that's
considered new and you can slap a 2016 on it.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_PROFILES_PROFILE_STATISTICS_CONSTANTS_H_
+#define CHROME_BROWSER_PROFILES_PROFILE_STATISTICS_CONSTANTS_H_
+
+namespace profiles {
+// Constants for the categories in ProfileCategoryStats
+extern const char kProfileStatisticsBrowsingHistory[];
+extern const char kProfileStatisticsPasswords[];
+extern const char kProfileStatisticsBookmarks[];
+extern const char kProfileStatisticsSettings[];
+}  // namespace profiles
+
+#endif  // CHROME_BROWSER_PROFILES_PROFILE_STATISTICS_CONSTANTS_H_