It contains an error ( https://code.google.com/p/android/issues/detail?id=57020 ) when someone from Google provides a pretty good answer.
The package you contacted is one of the packages contained in the Android Open Source Project (AOSP), and is usually created by the AOSP build system (not Android Studio or Eclipse). Thus, it may contain things that Android Studio cannot process (for example, duplicate lines and links to hidden APIs).
Basically, a duplicate line is what the Android build system (AOSP) handles internally through post-processing and is usually not allowed in normal application projects.
You can probably get around this, but a little modification of the sources may be required.
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