Fix proguard flags.
diff --git a/proguard.flags b/proguard.flags
new file mode 100644
index 0000000..0a5d2dd
--- /dev/null
+++ b/proguard.flags
@@ -0,0 +1,3 @@
+-keep class com.android.inputmethod.latin.BinaryDictionary {
+  int mDictLength;
+}