Move locale-related utility methods to LocaleUtils.

...d/deprecated/languageswitcher/InputLanguageSelection.java

...tmethod/deprecated/languageswitcher/LanguageSwitcher.java

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

...com/android/inputmethod/latin/BinaryDictionaryGetter.java

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

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

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

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

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

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

...utmethod/latin/spellcheck/AndroidSpellCheckerService.java

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