Add session parameter to OEMCrypto_CopyBuffer

Merge from master branch of Widevine repo of http://go/wvgerrit/66070
Merge from oemcrypto-v15 branch of Widevine repo of http://go/wvgerrit/63662

To make the threading model more clear, CopyBuffer is now a session function.
This means we need to pass in which session the current thread locks.

Test: unit tests.
Test: tested as part of http://go/ag/5501993
Bug: 113680369
Change-Id: I2fdd2cfcaab99f3793950b3845941463675f5e4c

libwvdrmengine/cdm/core/include/oemcrypto_adapter.h

@@ -14,9 +14,6 @@ namespace wvcdm {
 // If one level is not available, the other will be used instead.
 OEMCryptoResult OEMCrypto_OpenSession(OEMCrypto_SESSION* session,
                                       SecurityLevel level);
-OEMCryptoResult OEMCrypto_CopyBuffer(
-    SecurityLevel level, const uint8_t* data_addr, size_t data_length,
-    OEMCrypto_DestBufferDesc* out_buffer, uint8_t subsample_flags);
 OEMCryptoResult OEMCrypto_InstallKeybox(const uint8_t* keybox,
                                         size_t keyBoxLength,
                                         SecurityLevel level);