Add a triggered profile reset mechanism.

chrome/browser/profile_resetter/triggered_profile_resetter.h

+// 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 CHROME_BROWSER_PROFILE_RESETTER_TRIGGERED_PROFILE_RESETTER_H_
+#define CHROME_BROWSER_PROFILE_RESETTER_TRIGGERED_PROFILE_RESETTER_H_
+
+#include <string>
+
+#include "base/basictypes.h"

[grt (UTC plus 2), 2015/09/05 12:44:14]

nit: i think you really want macros.h rather than this for
DISALLOW_COPY_AND_ASSICN

+#include "base/logging.h"
+#include "base/memory/ref_counted.h"

[grt (UTC plus 2), 2015/09/05 12:44:14]

unused

+#include "base/memory/weak_ptr.h"

[grt (UTC plus 2), 2015/09/05 12:44:14]

unused

+#include "base/strings/string16.h"
+#include "components/keyed_service/core/keyed_service.h"
+
+class Profile;
+
+// This service is responsible for evaluating whether a profile reset trigger
+// has been set and not yet consumed by |profile_|. If it has, the profile is
+// eligible for reset and a profile reset UI will be show to the user. The
+// intended use case for this is to provide a sanctioned profile reset API for
+// third party tools (AVs or cleaner tools) that wish to reset users' profiles
+// as part of their cleanup flow.
+//
+// To use this mechanism from a third party tool, perform the following steps:
+//   1) Create (or open) the registry key
+//      HCKU\Software\$PRODUCT_STRING_PATH\TriggeredReset where
+//      $PRODUCT_NAME is one of the values in chrome\common\chrome_constants.h,
+//      currently either "Google\\Chrome" or "Chromium"
+//   2) Set a REG_SZ value called "ToolName" to the localized name of the tool.
+//      This string (truncated to kMaxToolNameLength) will be displayed in a
+//      notification UI.
+//   3) Set a REG_QWORD value with the timestamp of the reset. This value should
+//      be obtained from a call to ::GetSystemTimeAsFileTime(). This value
+//      will be persisted in a reset profile and will be used to avoid
+//      multiple resets.
+//
+// Some considerations:
+//
+// * Chrome supports multiple profiles. When the above steps are followed,
+//   each profile will enter the reset flow as it is opened.
+// * New profiles created while a timestamp is present will not get the reset
+//   flow.
+class TriggeredProfileResetter : public KeyedService {
+ public:
+  enum : int { kMaxToolNameLength = 100 };
+
+  explicit TriggeredProfileResetter(Profile* profile);
+  ~TriggeredProfileResetter() override;
+
+  // Causes the TriggeredProfileResetter to look for the presence of a trigger
+  // and perform a reset, subsequent calls to HasResetTrigger will return
+  // whether |profile_| is subject to a reset.
+  virtual void Activate();
+
+  // Returns true iff the given profile should have a reset reset according to
+  // the description in the class comment. Must call Activate() first.
+  virtual bool HasResetTrigger();

[grt (UTC plus 2), 2015/09/05 12:44:14]

very optional nit: you could get rid of virtual dispatch for this and the tool
name without hurting testability by making those two members protected. these
can both become inline functions in that case.

+
+  // Returns the name of the tool that performed the reset. This string will be
+  // truncated to a length of |kMaxToolNameLength|.
+  virtual base::string16 GetResetToolName();
+
+ private:
+  Profile* profile_;
+
+  bool has_reset_trigger_ = false;
+
+#if DCHECK_IS_ON()
+  bool activate_called_ = false;
+#endif
+
+  base::string16 tool_name_;
+
+  DISALLOW_COPY_AND_ASSIGN(TriggeredProfileResetter);
+};
+
+#endif  // CHROME_BROWSER_PROFILE_RESETTER_TRIGGERED_PROFILE_RESETTER_H_