fix possible NPE in DebugSettings

Change-Id: I44ec5bd3b2a00087603316f14d732164dbcf399f

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

@@ -107,6 +107,9 @@ public final class DebugSettings extends PreferenceFragment
         String version = "";
         try {
             final Context context = getActivity();
+            if (context == null) {
+                return;
+            }
             final String packageName = context.getPackageName();
             PackageInfo info = context.getPackageManager().getPackageInfo(packageName, 0);
             version = "Version " + info.versionName;