Fall back to L3 if L1 has test keybox

Merge from Widevine repo of http://go/wvgerrit/142150 (part 2)

For an EVT device, without a keybox or with a test keybox, we want it
to fall back to L3. However, when running the unit or integration
tests it should continue running tests with test keybox. This will
allow us to test L1 oemcrypto on an EVT device, while still using an
EVT device for dogfooding video content at the L3 level.

Bug: 210807585
Bug: 210823889
Change-Id: I30c35134239db35bb39f11f75220063181987763

libwvdrmengine/cdm/core/include/crypto_session.h

@@ -299,6 +299,10 @@ class CryptoSession {
   // report that it needs provisioning instead.
   static CdmResponseType SetDebugIgnoreKeyboxCount(uint32_t count);
 
+  // This tells the OEMCrypto adapter to allow the device to continue with a
+  // test keybox. Otherwise, the keybox is reported as invalid.
+  static CdmResponseType SetAllowTestKeybox(bool allow);
+
   // Returns a system-wide singleton instance of SystemFallbackPolicy
   // to be used for communicating OTA keybox provisioning state between
   // apps.  Returns a null pointer if OTA provisioning is not supported,
@@ -322,13 +326,10 @@ class CryptoSession {
   explicit CryptoSession(metrics::CryptoMetrics* crypto_metrics);
 
   int session_count() const { return session_count_; }
-  bool initialized() const { return initialized_; }
-  void set_initialized(bool initialized) { initialized_ = initialized; }
   // Cache api version and fallback policy. Call this once at initialization.
   void CacheVersion();
-  void OverrideNeedKeyboxForTesting(bool needs_keybox_provisioning) {
-    needs_keybox_provisioning_ = needs_keybox_provisioning;
-  }
+  // Re-initialize for running tests with a test keybox.
+  void ReinitializeForTest();
 
  private:
   friend class CryptoSessionForTest;