Fix SubtypeLocaleUtils.getSubtypeNameForLogging accepting null

Change-Id: Ic5cb55e24a2d843027ccc4e8e5d6954f9391c125
diff --git a/java/src/com/android/inputmethod/latin/utils/SubtypeLocaleUtils.java b/java/src/com/android/inputmethod/latin/utils/SubtypeLocaleUtils.java
index 013f024..0e7f471 100644
--- a/java/src/com/android/inputmethod/latin/utils/SubtypeLocaleUtils.java
+++ b/java/src/com/android/inputmethod/latin/utils/SubtypeLocaleUtils.java
@@ -34,6 +34,7 @@
 import java.util.Locale;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 
 /**
  * A helper class to deal with subtype locales.
@@ -273,7 +274,7 @@
     }
 
     @Nonnull
-    public static String getSubtypeNameForLogging(@Nonnull final InputMethodSubtype subtype) {
+    public static String getSubtypeNameForLogging(@Nullable final InputMethodSubtype subtype) {
         if (subtype == null) {
             return "<null subtype>";
         }