http://www.cnblogs.com/javadu/p/3812528.html
Android中AndroidManifest.xml警告
Should explicitly set android:allowBackup to true or false (it's true by default, and that can have some security implications for the application's data)
解决方案:
<application
android:allowBackup="true"
或
<application
android:allowBackup="false"
注意:android:allowBackup 必须是application中第一个标签键值对。
或者
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