[Win] Add a fast profile switcher to the Windows taskbar item.

chrome/browser/metrics/jumplist_metrics_win.h

+// Copyright 2014 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_METRICS_JUMPLIST_METRICS_WIN_H_
+#define CHROME_BROWSER_METRICS_JUMPLIST_METRICS_WIN_H_
+
+#include <string>
+
+namespace jumplist {
+
+// Enum for counting which category was clicked.
+// Note: UMA histogram enum - don't re-order or remove entries
+enum JumplistCategory {
+  RECENTLY_CLOSED_URL = 0,  // A URL from the "Recently Closed" category.
+  MOST_VISITED_URL,         // A URL from the "Most Visited" category.
+  SWITCH_TO_PROFILE,        // A profile name from the "People" category.
+  CATEGORY_UNKNOWN,         // An invalid category.
+  NUM_JUMPLIST_CATEGORY_METRICS
+};
+
+// Category types that can be logged with the --win-jumplist-action switch.
+extern const char kMostVisitedCategory[];
+extern const char kProfilesCategory[];
+extern const char kRecentlyClosedCategory[];
+
+// Logs a histogram for the JumplistCategory of the item that was clicked.
+void LogJumplistActionFromSwitchValue(const std::string& value);
+
+}  // namespace jumplist
+
+#endif  // CHROME_BROWSER_METRICS_JUMPLIST_METRICS_WIN_H_