Linux Android Debug Engine tries to build from flutter/testing/run_tests.py which is not taking advantage of goma and complicates the separation of builds and tests.

https://cs.opensource.google/flutter/engine/+/master:testing/run_tests.py;l=312
https://cs.opensource.google/flutter/engine/+/master:testing/run_tests.py;l=343
https://cs.opensource.google/flutter/engine/+/master:ci/analyze.sh;l=62

This is also making the depot_tools roll to fail:

https://ci.chromium.org/p/flutter/builders/try/recipes-with-led/b8844412153637241936?