media: release decoder explicitly instead of relying on GC.

Bug: 18835626
Change-Id: I6f5d7820ca4e936989e862b6812934942937dfa0
diff --git a/tests/tests/media/src/android/media/cts/NativeDecoderTest.java b/tests/tests/media/src/android/media/cts/NativeDecoderTest.java
index aed0029..e7b08e9 100644
--- a/tests/tests/media/src/android/media/cts/NativeDecoderTest.java
+++ b/tests/tests/media/src/android/media/cts/NativeDecoderTest.java
@@ -340,6 +340,10 @@
             }
         }
 
+        for (int i = 0; i < codec.length; i++) {
+            codec[i].release();
+        }
+
         return trackbytes;
     }