Componentize enhanced_bookmark_features.{h,cc}.

components/enhanced_bookmarks/enhanced_bookmark_switches.h

Index: components/enhanced_bookmarks/enhanced_bookmark_switches.h
diff --git a/components/enhanced_bookmarks/enhanced_bookmark_switches.h b/components/enhanced_bookmarks/enhanced_bookmark_switches.h
new file mode 100644
index 0000000000000000000000000000000000000000..9b93a4fabe251153aaf1b120347e7ea67eede6c5
--- /dev/null
+++ b/components/enhanced_bookmarks/enhanced_bookmark_switches.h
@@ -0,0 +1,14 @@
+// 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_ENHANCED_BOOKMARKS_ENHANCED_BOOKMARK_SWITCHES_H_
+#define COMPONENTS_ENHANCED_BOOKMARKS_ENHANCED_BOOKMARK_SWITCHES_H_
+
+namespace switches {
+
+extern const char kEnhancedBookmarksExperiment[];
+
+}  // namespace switches
+
+#endif  // COMPONENTS_ENHANCED_BOOKMARKS_ENHANCED_BOOKMARK_SWITCHES_H_