编译Release版本的apk时，出现transformClassesAndResourcesWithProguardForRelease错误

Execution failed for task ':xxxxxx:transformClassesAndResourcesWithProguardForRelease'.

AS报的具体错误如下图

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':xxxxxx:transformClassesAndResourcesWithProguardForRelease'.
> Job failed, see logs for details

接着上面的保持继续查找

Warning: library class android.content.pm.PackageManager depends on program class android.content.pm.IPackageDataObserver
Warning: library class android.content.pm.PackageManager depends on program class android.content.pm.IPackageDataObserver
Warning: library class android.content.pm.PackageManager depends on program class android.content.pm.IPackageDataObserver

对应自己的工程一看，发现自己把android.content.pm.PackageManager放到了aidl里面，却没有对其加混淆保护。在proguard-rules.pro里面增加下面的代码即可正常编译通过

-dontwarn android.content.pm.**
-keep class android.content.pm.** { *;}