Changes from Widevine CDM repo

Squashed commit of these CLs from the widevine cdm repo:

Update YT CP server URI to point to the UAT server
https://widevine-internal-review.googlesource.com/#/c/9327/

OEMCrypto Version 9 API
https://widevine-internal-review.googlesource.com/#/c/9142/

Correct Device ID length in OEMCrypto reference version
https://widevine-internal-review.googlesource.com/#/c/8723/

Modify tests to prevent intermittent failures
https://widevine-internal-review.googlesource.com/#/c/8982/

Generate a unique license request ID
https://widevine-internal-review.googlesource.com/#/c/8721/

Re-enable android timer mechanisms
https://widevine-internal-review.googlesource.com/#/c/8833/

Do not close CDM session on removeKeys
https://widevine-internal-review.googlesource.com/#/c/8703/

And numerous changes required by Eureka, Steel, and CTE versions of
Widevine CDM, as highlighted here:
https://widevine-internal-review.googlesource.com/#/c/8596/
https://widevine-internal-review.googlesource.com/#/c/8955/
https://widevine-internal-review.googlesource.com/#/c/8922/
https://widevine-internal-review.googlesource.com/#/c/8890/
https://widevine-internal-review.googlesource.com/#/c/8871/
https://widevine-internal-review.googlesource.com/#/c/8706/
https://widevine-internal-review.googlesource.com/#/c/8425/

Change-Id: Iafd33905227e74eb2132c240b929d2282ab68042

libwvdrmengine/cdm/core/include/policy_engine.h

@@ -27,7 +27,12 @@ class PolicyEngine {
   // status is not calculated to avoid overhead in the decryption path.
   inline bool can_decrypt()         { return can_decrypt_; }
 
-  void OnTimerEvent(bool& event_occurred, CdmEventType& event);
+  // OnTimerEvent is called when a timer fires. It notifies the Policy Engine
+  // that the timer has fired and that it should check whether any events have
+  // occurred since the last timer event. If so, it sets event_occurred to true
+  // and sets event to point to the event that occurred. If not, it sets
+  // event_occurred to false.
+  void OnTimerEvent(bool* event_occurred, CdmEventType* event);
 
   // SetLicense is used in handling the initial license response. It stores
   // an exact copy of the policy information stored in the license.