Move shorcut IME related code from SubtypeSwitcher to RichInputMethodManager

...rc/com/android/inputmethod/keyboard/KeyboardSwitcher.java

java/src/com/android/inputmethod/latin/LatinIME.java

...com/android/inputmethod/latin/RichInputMethodManager.java

java/src/com/android/inputmethod/latin/SubtypeSwitcher.java

...putmethod/latin/settings/PreferencesSettingsFragment.java

...om/android/inputmethod/latin/settings/SettingsValues.java