Fix exported property on NotificationBroadcastReceiver.

"exported" property was missing "android:" prefix and as a result was
not being respected.

bug:11367588
Change-Id: I71b851c94306a2ac4b727a735de07103eb35b6e6
(cherry picked from commit 0c88ac2ffff5472f49f48cad08e89215ec737c16)
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 4f9dbfb..2721a8b 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -538,7 +538,7 @@
         </receiver>
 
         <!-- BroadcastReceiver for receiving Intents from Notification mechanism. -->
-        <receiver android:name="PhoneGlobals$NotificationBroadcastReceiver" exported="false">
+        <receiver android:name="PhoneGlobals$NotificationBroadcastReceiver" android:exported="false">
             <intent-filter>
                 <action android:name="com.android.phone.ACTION_HANG_UP_ONGOING_CALL" />
                 <action android:name="com.android.phone.ACTION_CALL_BACK_FROM_NOTIFICATION" />