Avoid a leak in AudioCodingModuleTest.TestIsac. The leak was caught by LSAN.

BUG=2515
TEST=reproduced locally on linux and verified the fix resolves the issue.
R=henrik.lundin@webrtc.org, kjellander@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2499004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5048 4adac7df-926f-26a2-2b94-8c16560cd09d
2 files changed