cronet: enable defaults in aosp

Automerger into tm-mainline-prod is currently broken, so this change
uses a Merged-In line that is already present in tm-mainline-prod (and
downstream from it). This means that this change must also be
cherry-picked into internal-master with a slightly different Merged-In
specification.

Test: TH
Merged-In: I555ad1ed687632cfe8a7e30283f80e80956fc1d4
Change-Id: I25096f4cc21923c602d77a66aad248d52b42b18f
1 file changed