We should switch the keyboard layout to the layout the user set according to

chromeos/ime/input_methods.txt

Index: chromeos/ime/input_methods.txt
diff --git a/chromeos/ime/input_methods.txt b/chromeos/ime/input_methods.txt
index 85ee9b93c409ae32c7b14002e8f36c0d2c2d61e7..ff7b35c857830a3da470d4db32cc2b223188f5fb 100644
--- a/chromeos/ime/input_methods.txt
+++ b/chromeos/ime/input_methods.txt
@@ -56,6 +56,17 @@
 #   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 a new language such that all its layouts can be used at
+#   signin screen (e.g. it is "Full Latin Keyboard Language" therefore allowing
+#   input of gmail password), you should also update
+#   kFullLatinKeyboardLanguageList[] in chrome/browser/chromeos/input_method/
+#   input_method_manager_impl.cc .
+#
+#   If you add a new keyboard layout for existing language, please ensure
+#   that its "Full Latin Keyboard Language" property is not changed by new
+#   layout. If it's changed, please also update kFullLatinKeyboardLanguageList[]
+#   or change algoritm to check "this input method can be used at login screen".
 
 # U.S. English
 xkb:us::eng	us	en-US