StagefrightTest: call codec.stop() before codec.release() Add missing codec.stop() before calling codec.release() in doStagefrightTestMediaCodec() Bug: 65483665 Bug: 160346309 Fix: 194287163 Test: atest \ android.security.cts.StagefrightTest#testStagefright_bug_65483665 Change-Id: I6571c2be5a48bc1e631110cc09560655576059bf (cherry picked from commit 81e2ae63b96c31c0c7e8f2fdace956cf0f3572ed) (cherry picked from commit 6c1316019d9a34ce6492292ec4b9c9c6c10f6884)