mac: Create a static mapping of accelerators in the main menu.

ui/events/keycodes/keyboard_code_conversion_mac.mm

 // 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.
 
 #import "ui/events/keycodes/keyboard_code_conversion_mac.h"
 
 #include <algorithm>
 
 #import <Carbon/Carbon.h>
 
@@ skipping 503 matching lines @@
           break;
         case kVK_ANSI_Slash:
           *character = '?';
           break;
         default:
           break;
       }
     }
   }
 
-  // Control characters.

[erikchen, 2014/02/11 05:09:22]

This code is not used in the current code base (All calls to
MacKeyCodeForWindowsKeyCode use flags = 0). 

I don't understand lines 526-527, despite having looked at the CL in which this
code was introduced. https://codereview.chromium.org/2986004. This code causes
my newly written code to malfunction, so I removed it.

-  if (flags & NSControlKeyMask) {
-    if (keycode >= VKEY_A && keycode <= VKEY_Z)
-      *character = 1 + keycode - VKEY_A;
-    else if (macKeycode == kVK_ANSI_LeftBracket)
-      *character = 27;
-    else if (macKeycode == kVK_ANSI_Backslash)
-      *character = 28;
-    else if (macKeycode == kVK_ANSI_RightBracket)
-      *character = 29;
-  }
-
   // TODO(suzhe): Support characters for Option key bindings.
   return macKeycode;
 }
 
 KeyboardCode KeyboardCodeFromNSEvent(NSEvent* event) {
   KeyboardCode code = VKEY_UNKNOWN;
 
   if ([event type] == NSKeyDown || [event type] == NSKeyUp) {
     NSString* characters = [event characters];
     if ([characters length] > 0)
       code = KeyboardCodeFromCharCode([characters characterAtIndex:0]);
     if (code)
       return code;
 
     characters = [event charactersIgnoringModifiers];
     if ([characters length] > 0)
       code = KeyboardCodeFromCharCode([characters characterAtIndex:0]);
     if (code)
       return code;
   }
   return KeyboardCodeFromKeyCode([event keyCode]);
 }
 
 const char* CodeFromNSEvent(NSEvent* event) {
   return KeycodeConverter::GetInstance()->NativeKeycodeToCode(
       [event keyCode]);
 }
 
 }  // namespace ui