Orchestrator fails if service disconnects

Description

Our test suite has recently begun crashing without running all the tests.

From logcat, it looks like we are running into memory pressure and Android is killing the Orchestration Service.

The OrchestratedInstrumentationListener code does not trigger a reconnect to the service on disconnect, and this makes tests fail if the service is killed. Once the service is killed there is no way to recover. The code should be updated to rebind the service on an unbind.

In addition the service is not being bound with flag Service.BIND_IMPORTANT which would make the Orchestration Service less likely to be killed under memory pressure.

Steps to Reproduce

I have outlined steps to reproduce here:
https://issuetracker.google.com/issues/135574731

Note that you may have to add tests which consume memory to cause the service to be killed.

Expected Results

The orchestrator does not crash.

Actual Results

The orchestrator crashes and only a small subset of our tests are run.

AndroidX Test and Android OS Versions

AndroidX 1.2.0 - Tested on both 26 and 27.

Comienza con OrchestratedInstrumentationListener y el código de vinculación del servicio, y luego sigue los pasos de reproducción de issuetracker.google.com/issues/135574731 en AndroidX Test 1.2.0 con Android 26 o 27. Verifica el comportamiento cuando Android finaliza el Orchestration Service bajo presión de memoria; se considera terminado cuando el servicio se vuelve a vincular después de unbind, se vincula con Service.BIND_IMPORTANT y la suite de pruebas completa continúa ejecutándose.