Better debug info for obsolete API: When the Android Gradle plugin warns you that you're using API that's no longer supported, it can now provide more detailed information to help you determine where that API is being used. To see the additional info, you need to include the following in your project's gradle.properties file:
android.debug.obsoleteApi=true
You can also enable the flag by passing -Pandroid.debug.obsoleteApi=true from the command line.