Restart background executor.

Bug 19671650.

Change-Id: I1a28a53e94bdb79aeb173f6905c1035022495acc
diff --git a/java/src/com/android/inputmethod/latin/utils/ExecutorUtils.java b/java/src/com/android/inputmethod/latin/utils/ExecutorUtils.java
index 3a6c60b..9171468 100644
--- a/java/src/com/android/inputmethod/latin/utils/ExecutorUtils.java
+++ b/java/src/com/android/inputmethod/latin/utils/ExecutorUtils.java
@@ -33,7 +33,7 @@
 
     private static final String TAG = "ExecutorUtils";
 
-    private static final ScheduledExecutorService sExecutorService =
+    private static ScheduledExecutorService sExecutorService =
             Executors.newSingleThreadScheduledExecutor(new ExecutorFactory());
 
     private static class ExecutorFactory implements ThreadFactory {
@@ -80,6 +80,8 @@
         } catch (InterruptedException e) {
             Log.wtf(TAG, "Failed to shut down background task.");
             throw new IllegalStateException("Failed to shut down background task.");
+        } finally {
+            sExecutorService = Executors.newSingleThreadScheduledExecutor(new ExecutorFactory());
         }
     }