Update StickyKeys overlay to show or hide AltGr depending on the

chromeos/ime/input_methods.txt

 # The list of keyboard layouts that we support. The keyboard layout metadata is
 # also defined here.
 #
 # Each non-comment line contains the following tab-or-space-separated columns.
 #
 # 1) The input method ID used by Chrome. (ex. "xkb:ca::fra") You should *NEVER*
 #    change the ID since the ID might be written in user's ~/Preferences. For
 #    example, three-letter ISO 639-2/B codes are used for IDs start with "xkb:"
 #    for histrical reason, but we should not replace them with two-letter 639-1
 #    codes that are currently in use in the 3rd column.
@@ skipping 16 matching lines @@
 #   method ID to the keyboard overlay ID to INPUT_METHOD_ID_TO_OVERLAY_ID in
 #
 #    * tools/gen_keyboard_overlay_data/gen_keyboard_overlay_data.py
 #
 #   and update the following files by running this script.
 #
 #    * chrome/app/generated_resources.grd
 #    * chrome/browser/resources/chromeos/keyboard_overlay_data.js
 #    * chrome/browser/ui/webui/chromeos/keyboard_overlay_ui.cc
 #
-#   If you add an XKB layout which depends on X11's Mod3Mask (e.g. Germany Neo2
-#   XKB layout), you should also update IsMod3UsedByCurrentInputMethod() method
-#   in chrome/browser/ui/ash/event_rewriter.cc. Otherwise, Mod3Mask might be
-#   removed unexpectedly by the rewriter.
+#   If you add an XKB layout which depends on AltGr or X11's Mod3Mask
+#   (e.g. Germany Neo2 XKB layout), you should also update kAltGrLayoutIds or
+#   kMod3LayoutIds in
+#   chrome/browser/chromeos/input_method/input_method_manager_impl.cc
+#   Otherwise, Mod3Mask might be removed unexpectedly by the rewriter, and
+#   sticky keys will not work.
 #
 
 # U.S. English
 xkb:us::eng           us             en-US,en-AU,id,fil,ms US   login
 xkb:us:intl:eng       us(intl)       en-US,nl,pt-BR        INTL login
 xkb:us:altgr-intl:eng us(altgr-intl) en-US                 EXTD login
 xkb:us:dvorak:eng     us(dvorak)     en-US                 DV   login
 xkb:us:colemak:eng    us(colemak)    en-US                 CO   login
 # U.S. English entiries have to be above the Dutch entry so that xkb:us:intl:eng
 # will be selected as the default keyboard when the UI language is set to Dutch.
@@ skipping 56 matching lines @@
 xkb:si::slv           si             sl        SI login
 xkb:rs::srp           rs             sr        RS
 xkb:tr::tur           tr             tr        TR login
 xkb:ua::ukr           ua             uk        UA
 xkb:by::bel           by             be        BY
 xkb:am:phonetic:arm   am             hy        AM
 xkb:ge::geo           ge             ka        GE
 xkb:mn::mon           mn             mn        MN
 # TODO(yusukes): Support xkb:latam:deadtilde:spa and/or xkb:latam:nodeadkeys:spa
 # if necessary.