Add power-user keyboard mode for ChromeOS with Search key acting as a typical Fn key.

chrome/browser/ui/ash/event_rewriter.h

 // Copyright (c) 2012 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_UI_ASH_EVENT_REWRITER_H_
 #define CHROME_BROWSER_UI_ASH_EVENT_REWRITER_H_
 
 #include <map>
 #include <string>
 
@@ skipping 98 matching lines @@
   // Rewrites a NumPad key press/release without Num Lock to a corresponding key
   // press/release with the lock.  Returns true when |event| is rewritten.
   bool RewriteNumPadKeys(ui::KeyEvent* event);
 
   // Rewrites Backspace and Arrow keys following the Chrome OS keyboard spec.
   //  * Alt+Backspace -> Delete
   //  * Alt+Up -> Prior (aka PageUp)
   //  * Alt+Down -> Next (aka PageDown)
   //  * Ctrl+Alt+Up -> Home
   //  * Ctrl+Alt+Down -> End
+  // When the Search key acts as a function key, it instead maps:
+  //  * Search+Backspace -> Delete
+  //  * Search+Up -> Prior (aka PageUp)
+  //  * Search+Down -> Next (aka PageDown)
+  //  * Search+Left -> Home
+  //  * Search+right -> End
+  // Returns true when the |event| is rewritten.
   bool RewriteBackspaceAndArrowKeys(ui::KeyEvent* event);
 
   // Rewrites the located |event|.
   void RewriteLocatedEvent(ui::LocatedEvent* event);
 
   // Overwrites |event| with the keycodes and flags.
   void OverwriteEvent(ui::KeyEvent* event,
                       unsigned int new_native_keycode,
                       unsigned int new_native_state,
                       ui::KeyboardCode new_keycode,
@@ skipping 46 matching lines @@
 
   chromeos::input_method::XKeyboard* xkeyboard_;  // for testing.
 #endif
 
   const PrefService* pref_service_;  // for testing.
 
   DISALLOW_COPY_AND_ASSIGN(EventRewriter);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_EVENT_REWRITER_H_