Merge CE Device Changes

This is a merge of the following changes made for CE devices in the
widevine share repo:

http://go/wvgerrit/16211 Only load offline session if needed in GKR
http://go/wvgerrit/16245 Unreserve IDs in reservation test
http://go/wvgerrit/16242 Re-enable WebM tests
http://go/wvgerrit/16240 Un-reserve reserved license IDs
http://go/wvgerrit/16190 Add temporary session type
http://go/wvgerrit/16189 Enforce license type and can_persist for storage

Change-Id: I592416f66c0d1286844266c01cc9b4906c7b6b05

libwvdrmengine/cdm/core/src/cdm_engine.cpp

@@ -228,7 +228,8 @@ CdmResponseType CdmEngine::GenerateKeyRequest(
 
   key_request->clear();
 
-  if (license_type == kLicenseTypeRelease) {
+  if (license_type == kLicenseTypeRelease &&
+      !iter->second->license_received()) {
     sts = iter->second->RestoreOfflineSession(key_set_id, kLicenseTypeRelease);
     if (sts != KEY_ADDED) {
       LOGE("CdmEngine::GenerateKeyRequest: key release restoration failed,"