Define TAG in LoopbackExperiment

Previously LoopbackExperiment used the base class's TAG, but we've
defined one in LoopbackExperiment in favor of specificity.

In addition, this fixes errors created by proguard when building with
OpenJDK.

Change-Id: I6338f6499fbb4664988058e4f202b45d4fb80c1d
diff --git a/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/Experiment.java b/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/Experiment.java
index 6f2aa83..bd5f186 100644
--- a/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/Experiment.java
+++ b/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/Experiment.java
@@ -27,7 +27,7 @@
  * The base class for all audio experiments.
  */
 public class Experiment implements Runnable {
-    protected static final String TAG = "AudioQualityVerifier";
+    private static final String TAG = "AudioQualityVerifier";
 
     private static final int DEFAULT_TIMEOUT = 5; // In seconds
 
diff --git a/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/experiments/LoopbackExperiment.java b/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/experiments/LoopbackExperiment.java
index 16039cb..a5c41be 100644
--- a/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/experiments/LoopbackExperiment.java
+++ b/apps/CtsVerifier/src/com/android/cts/verifier/audioquality/experiments/LoopbackExperiment.java
@@ -34,6 +34,8 @@
  * the test results (score and report).
  */
 public class LoopbackExperiment extends Experiment {
+    private static final String TAG = "LoopbackExperiment";
+
     protected static final int TIMEOUT = 10;
 
     // Amount of silence in ms before and after playback