Settings to remap Backspace and Escape keys

chrome/browser/chromeos/events/event_rewriter.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_CHROMEOS_EVENTS_EVENT_REWRITER_H_
 #define CHROME_BROWSER_CHROMEOS_EVENTS_EVENT_REWRITER_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 16 matching lines @@
 enum class DomCode;
 };
 
 namespace chromeos {
 namespace input_method {
 class ImeKeyboard;
 }
 
 // EventRewriter makes various changes to keyboard-related events,
 // including KeyEvents and some other events with keyboard modifier flags:
-// - maps modifiers keys (Control, Alt, Search, Caps, Diamond) according
-//   to user preferences;
+// - maps modifiers keys (Control, Alt, Search, Caps Lock, Escape, Backspace
+//   Diamond) according to user preferences;

[stevenjb, 2016/08/17 22:35:30]

Are Esc/Backspace considered 'modifier keys'? The others don't typically do
things on their own (with the exception of caps lock/search, but that's kind of
a funky exception for chrome os).

[michaelpg, 2016/08/17 23:00:58]

Technically, no. (Caps Lock is normally also not considered a modifier.) But
they're mappable to modifier keys, and in this particular implementation, make
the most sense to handle in the same place as modifier keys.

[stevenjb, 2016/08/17 23:04:08]

OK, thanks for clarifying the comment.

 // - maps Command to Control on Apple keyboards;
 // - converts numeric pad editing keys to their numeric forms;
 // - converts top-row function keys to special keys where necessary;
 // - handles various key combinations like Search+Backspace -> Delete
 //   and Search+number to Fnumber;
 // - handles key/pointer combinations like Alt+Button1 -> Button3.
 class EventRewriter : public ui::EventRewriter {
  public:
   enum DeviceType {
     kDeviceUnknown = 0,
@@ skipping 151 matching lines @@
   int pressed_modifier_latches_;
   int latched_modifier_latches_;
   int used_modifier_latches_;
 
   DISALLOW_COPY_AND_ASSIGN(EventRewriter);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_EVENTS_EVENT_REWRITER_H_