missing synchronization fix

Bugfix 2622197.

Modification of the static mListeners (hashmap) is synchronized on the ContactsCache
class object.  This was missing, however, when we clone the hashmap in order to
send out updates.  Cloning is done in case the callback modifies the list of listeners.

Change-Id: Ic09aaee91e448c4a7d610b6f72ad8122fefef7da

src/com/android/mms/data/Contact.java

@@ -523,7 +523,12 @@ private void updateContact(final Contact c) {
 
                     // clone the list of listeners in case the onUpdate call turns around and
                     // modifies the list of listeners
-                    for (UpdateListener l : (HashSet<UpdateListener>)Contact.mListeners.clone()) {
+                    // access to mListeners is synchronized on ContactsCache
+                    HashSet<UpdateListener> iterator;
+                    synchronized (ContactsCache.class) {
+                        iterator = (HashSet<UpdateListener>)Contact.mListeners.clone();
+                    }
+                    for (UpdateListener l : iterator) {
                         if (V) Log.d(TAG, "updating " + l);
                         l.onUpdate(c);
                     }