Revert "Cronet: Simplify Android GN logic for srcjars by not using them"

This reverts commit 27bd2d6ffb68067d7b771524ece94cf9a579f00c.

Reason for revert: Broke this bot:
https://logs.chromium.org/logs/chrome/bb/internal.client.clank/arm-builder/18748/+/recipes/steps/compile/0/stdout

Original change's description:
> Cronet: Simplify Android GN logic for srcjars by not using them
> 
> No need to zip up the generated source just to unzip it again :P
> 
> Bug: 908479
> Change-Id: Iac6982eb4b436a7e33c53b79f239fe2954fa4f11
> Reviewed-on: https://chromium-review.googlesource.com/c/1349871
> Commit-Queue: agrieve <agrieve@chromium.org>
> Reviewed-by: Paul Jensen <pauljensen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#610889}

TBR=pauljensen@chromium.org,agrieve@chromium.org

Change-Id: I9daab0436aa1ff7605f427ab815adff711c0d59d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 908479
Reviewed-on: https://chromium-review.googlesource.com/c/1351575
Reviewed-by: agrieve <agrieve@chromium.org>
Commit-Queue: agrieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#610938}
1 file changed