make update-api

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You have tried to change the API from what has been previously approved.

To make these errors go away, you have two choices:
   1) You can add "@hide" javadoc comments to the methods, etc. listed
in the
      errors above.

   2) You can update current.xml by executing the following commands:

         p4 edit frameworks/base/api/current.xml
         make update-api

      To check in the revised current.xml, you will need OWNERS
approval.
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如果自己添加了Android API 那么编译系统会出现此错误， 解决办法：

先 make update-api 然后再make -j4 直接就可编译成功