[ Merge of http://go/ag/5334065 and http://go/wvgerrit/65122 ] Sessions were not being correctly released when CloseCdm() was called. Broadcom noticed this issue and proposed the fix. Bug: 117876077 Test: WV unit/integration tests, GtsMediaTestCases and playback tests Change-Id: I8800744f2396f0955c76d5f3e187a69fe04330f6