Prevent receiver leak in TrustAgentWrapper

Bug: 19601687
Change-Id: Idfe5429926e1c849dc2d908b4877d8410335391c
diff --git a/services/core/java/com/android/server/trust/TrustAgentWrapper.java b/services/core/java/com/android/server/trust/TrustAgentWrapper.java
index 57b204d..583cc6b 100644
--- a/services/core/java/com/android/server/trust/TrustAgentWrapper.java
+++ b/services/core/java/com/android/server/trust/TrustAgentWrapper.java
@@ -395,6 +395,7 @@
     }
 
     public void destroy() {
+        mContext.unregisterReceiver(mBroadcastReceiver);
         mHandler.removeMessages(MSG_RESTART_TIMEOUT);
 
         if (!mBound) {