Downstream, we aggressively delete res/ files from play services in order to save space:

https://cs.chromium.org/chromium/src/build/android/play_services/preprocess.py

We don't get much coverage of this filtering though, since we don't apply it to chrome_public_apk and friends.

We should apply it consistently.

Related bugs:
Use AARs for gmscore clients downstream: bug 668211
Add Resource Shrinking to our Android build rules: bug 636448