Add audio health tests.

First test for audio health check. The test checks if all declared
devices found by checking if the audio device types of attached devices
can be seen by audio policy.

Bug: 141580284
Test: atest audio_health_tests audiopolicy_tests
Change-Id: I0374f382eaab7b36ab623b11a59e0634565f2187
diff --git a/services/audiopolicy/tests/AudioPolicyTestManager.h b/services/audiopolicy/tests/AudioPolicyTestManager.h
index ba1412b..bafcc63 100644
--- a/services/audiopolicy/tests/AudioPolicyTestManager.h
+++ b/services/audiopolicy/tests/AudioPolicyTestManager.h
@@ -24,6 +24,7 @@
     explicit AudioPolicyTestManager(AudioPolicyClientInterface *clientInterface)
             : AudioPolicyManager(clientInterface, true /*forTesting*/) { }
     using AudioPolicyManager::getConfig;
+    using AudioPolicyManager::loadConfig;
     using AudioPolicyManager::initialize;
     using AudioPolicyManager::getOutputs;
 };