Pass words as int[] to the native code.

We need to get the bigrams during the call to getSuggestions for
bug#6313806. We already give an int[] to getSuggestions and we
wanted to get rid of char[]'s anyway because it doesn't work with
surrogate pairs, so here we go.

Bug: 6313806
Change-Id: I56ce99f1db6b3302cdf42f0527343bded837091e
diff --git a/native/jni/src/bigram_dictionary.h b/native/jni/src/bigram_dictionary.h
index 1612131..07e47f0 100644
--- a/native/jni/src/bigram_dictionary.h
+++ b/native/jni/src/bigram_dictionary.h
@@ -25,10 +25,10 @@
 class BigramDictionary {
  public:
     BigramDictionary(const unsigned char *dict, int maxWordLength, Dictionary *parentDictionary);
-    int getBigrams(unsigned short *word, int length, int *codes, int codesSize,
+    int getBigrams(const int32_t *word, int length, int *codes, int codesSize,
             unsigned short *outWords, int *frequencies, int maxWordLength, int maxBigrams);
     int getBigramListForWord(const uint8_t* const root,
-        const unsigned short *prevWord, const int prevWordLength);
+        const int32_t *prevWord, const int prevWordLength);
     ~BigramDictionary();
  private:
     bool addWordBigram(unsigned short *word, int length, int frequency);