The recent runs of android_cronet_tester trybot have failed with the following error during the compilation step:

waiting for compiler_proxy...
compiler proxy (pid=14777) status: http://127.0.0.1:8088 error: timed out to send request to backend servers
Traceback (most recent call last):
  File "/b/build/slave/cache/cipd/goma/goma_ctl.py", line 2441, in <module>
    sys.exit(main())
...
  File "/b/build/slave/cache/cipd/goma/goma_ctl.py", line 671, in _GenericStartCompilerProxy
    raise Error('Failed to start compiler_proxy successfully.')
__main__.Error: Failed to start compiler_proxy successfully.

Here is the link:
https://build.chromium.org/p/tryserver.chromium.android/builders/android_cronet_tester/builds/656