[AC1] Add a memory of where to cut the first word.

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

...c/com/android/inputmethod/latin/ExpandableDictionary.java

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

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

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

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

tests/src/com/android/inputmethod/latin/InputTestsBase.java

...rc/com/android/inputmethod/latin/SuggestedWordsTests.java