Replace Chinese Input with migration code.

chromeos/ime/input_methods.txt

 # The list of input methods that we support. The input methods metadata is
 # also defined here. We use this data for the following purposes.
 #
 # 1. Exclude unnecessary input methods. For example, we don't need
 #    "ja:anthy", and "zh:pinyin" engines in ibus-m17n since we have better
 #    alternatives outside of ibus-m17n. Excluding these input methods from
 #    the IBus engine XML files, such as /usr/share/ibus/component/m17n.xml,
 #    makes the startup time of the IBus daemon faster. This filtering is
 #    done using a python script at build time of ibus-m17n.
 #    See crosbug.com/4161 for details.
@@ skipping 80 matching lines @@
 
 # Russian
 xkb:ru::rus     ru      ru      
 xkb:ru:phonetic:rus     ru(phonetic)    ru      
 
 # Thai
 m17n:th:kesmanee        us      th
 m17n:th:pattachote      us      th
 m17n:th:tis820  us      th
 
-# Simplified Chinese
-pinyin  us      zh-CN
-pinyin-dv       us(dvorak)      zh-CN   
-
 # Traditional Chinese
-mozc-chewing    us      zh-TW
-m17n:zh:cangjie us      zh-TW
 m17n:zh:quick   us      zh-TW
 
 # Vietnamese
 m17n:vi:tcvn    us      vi
 m17n:vi:telex   us      vi
 m17n:vi:viqr    us      vi
 m17n:vi:vni     us      vi
 # Note: Since Chrome does not support "get surrounding text" feature yet,
 # Vietnames input methods, except 4 input methods above, in m17n-db should
 # not work fine. The 4 input methods in m17n-db (>= 1.6.0) don't require the
@@ skipping 89 matching lines @@
 xkb:si::slv     si      sl      
 xkb:rs::srp     rs      sr      
 xkb:tr::tur     tr      tr      
 xkb:ua::ukr     ua      uk      
 xkb:by::bel     by      be
 xkb:am:phonetic:arm     am      hy
 xkb:ge::geo     ge      ka
 xkb:mn::mon     mn      mn
 # TODO(yusukes): Support xkb:latam:deadtilde:spa and/or xkb:latam:nodeadkeys:spa
 # if necessary.