OEMCrypto Mock SRM functionality

Merge from Widevine repo of http://go/wvgerrit/24730

This CL adds SRM functionality to the modable version of oemcrypto
mock.  This can be used for end-to-end testing.

b/28955873
b/37353534

Change-Id: I2c6f513495ccfd42f7a3d7a3449db6f810563c04

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_mock.h

@@ -123,6 +123,23 @@ class CryptoEngine {
   // If 0 no restriction, otherwise it's the max buffer for DecryptCENC.
   virtual size_t max_buffer_size() { return 1024 * 100; }  // 100 KiB.
 
+  virtual bool srm_update_supported() { return false; }
+
+  virtual OEMCryptoResult current_srm_version(uint16_t* version) {
+    return OEMCrypto_ERROR_NOT_IMPLEMENTED;
+  }
+
+  virtual OEMCryptoResult load_srm(const uint8_t* buffer,
+                                   size_t buffer_length) {
+    return OEMCrypto_ERROR_NOT_IMPLEMENTED;
+  }
+
+  virtual OEMCryptoResult remove_srm() {
+    return OEMCrypto_ERROR_NOT_IMPLEMENTED;
+  }
+
+  virtual bool srm_blacklisted_device_attached() { return false; }
+
   // Set destination pointer based on the output destination description.
   OEMCryptoResult SetDestination(OEMCrypto_DestBufferDesc* out_description,
                                  size_t data_length, uint8_t subsample_flags);