Cronet extension project setup
Cronet extension project setup

- Add build test to [] so it runs in presubmit
- Tweak README.md instructions
- Use symlinks to make the extension usable in Android
  Studio internally, without taking any special action
- Remove unnecessary dependencies
- Simplify setup instructions in README.md

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=129733466

stari4ek/ExoPlayer,michalliu/ExoPlayer,jeoliva/ExoPlayer,ened/ExoPlayer,ebr11/ExoPlayer,MaTriXy/ExoPlayer,YouKim/ExoPlayer,google/ExoPlayer,jeoliva/ExoPlayer,rubensousa/exoplayer-amazon-port,barbarian/ExoPlayer,yangwuan55/ExoPlayer,amzn/exoplayer-amazon-port,KiminRyu/ExoPlayer,zhouweiguo2017/ExoPlayer,stari4ek/ExoPlayer,MaTriXy/ExoPlayer,barbarian/ExoPlayer,jeoliva/ExoPlayer,zhouweiguo2017/ExoPlayer,JasonFengHot/ExoPlayerSource,Ood-Tsen/ExoPlayer,superbderrick/ExoPlayer,kiall/ExoPlayer,yangwuan55/ExoPlayer,MaTriXy/ExoPlayer,kiall/ExoPlayer,fanhattan/ExoPlayer,saki4510t/ExoPlayer,ebr11/ExoPlayer,ClubCom/AndroidExoPlayer,KiminRyu/ExoPlayer,Ood-Tsen/ExoPlayer,ebr11/ExoPlayer,google/ExoPlayer,androidx/media,ened/ExoPlayer,google/ExoPlayer,superbderrick/ExoPlayer,androidx/media,androidx/media,tntcrowd/ExoPlayer,tntcrowd/ExoPlayer,Ood-Tsen/ExoPlayer,amzn/exoplayer-amazon-port,barbarian/ExoPlayer,WeiChungChang/ExoPlayer,YouKim/ExoPlayer,jcable/ExoPlayer,rubensousa/exoplayer-amazon-port,yangwuan55/ExoPlayer,tntcrowd/ExoPlayer,JasonFengHot/ExoPlayerSource,ened/ExoPlayer,stari4ek/ExoPlayer,saki4510t/ExoPlayer,YouKim/ExoPlayer,zhouweiguo2017/ExoPlayer,fanhattan/ExoPlayer,YouKim/ExoPlayer,fanhattan/ExoPlayer,kiall/ExoPlayer,JasonFengHot/ExoPlayerSource,KiminRyu/ExoPlayer,WeiChungChang/ExoPlayer,superbderrick/ExoPlayer,michalliu/ExoPlayer,michalliu/ExoPlayer,saki4510t/ExoPlayer,ClubCom/AndroidExoPlayer,jcable/ExoPlayer,ClubCom/AndroidExoPlayer,amzn/exoplayer-amazon-port,WeiChungChang/ExoPlayer,jcable/ExoPlayer,rubensousa/exoplayer-amazon-port