Make the destructor of AudioCodingModule public.

This allows the type to be used with a scoped_ptr. Remove all calls to
the deprecated Destroy() from tests.

R=turaj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2200006

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4731 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/main/test/APITest.cc b/webrtc/modules/audio_coding/main/test/APITest.cc
index 90f88e3..cb7115e 100644
--- a/webrtc/modules/audio_coding/main/test/APITest.cc
+++ b/webrtc/modules/audio_coding/main/test/APITest.cc
@@ -55,8 +55,8 @@
 }
 
 APITest::APITest()
-    : _acmA(NULL),
-      _acmB(NULL),
+    : _acmA(AudioCodingModule::Create(1)),
+      _acmB(AudioCodingModule::Create(2)),
       _channel_A2B(NULL),
       _channel_B2A(NULL),
       _writeToFile(true),
@@ -111,9 +111,6 @@
 }
 
 APITest::~APITest() {
-  DESTROY_ACM(_acmA);
-  DESTROY_ACM(_acmB);
-
   DELETE_POINTER(_channel_A2B);
   DELETE_POINTER(_channel_B2A);
 
@@ -141,9 +138,6 @@
 }
 
 int16_t APITest::SetUp() {
-  _acmA = AudioCodingModule::Create(1);
-  _acmB = AudioCodingModule::Create(2);
-
   CodecInst dummyCodec;
   int lastPayloadType = 0;