L1 System Lowered to L3 Still Requires Secure Decoders

Merge of https://widevine-internal-review.googlesource.com/#/c/8263
from the Widevine repo.

Changes the behavior of requiresSecureDecoderComponent() to query the
session for whether a lowered security level has been requested
before querying the system to see what its default security level is.

As part of this, we added a new QuerySessionStatus() method to the
CDM that gets status info on a session-specific level, such as the
effective security level of a session.

Bug: 11428937
Change-Id: I5549a2fdd400cc87f567d27fcf74c473451093d6

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -65,6 +65,10 @@ class CdmEngine : public TimerHandler {
   // Query system information
   virtual CdmResponseType QueryStatus(CdmQueryMap* info);
 
+  // Query session information
+  virtual CdmResponseType QuerySessionStatus(const CdmSessionId& session_id,
+                                             CdmQueryMap* key_info);
+
   // Query license information
   virtual CdmResponseType QueryKeyStatus(const CdmSessionId& session_id,
                                          CdmQueryMap* key_info);

libwvdrmengine/cdm/core/include/cdm_session.h

@@ -49,6 +49,9 @@ class CdmSession {
   // CancelKeyRequest() - Cancel session.
   CdmResponseType CancelKeyRequest();
 
+  // Query session status
+  CdmResponseType QueryStatus(CdmQueryMap* key_info);
+
   // Query license information
   CdmResponseType QueryKeyStatus(CdmQueryMap* key_info);