SF: move idle timer to refresh rate configs

Move Idle timer management to RefreshRateConfigs to be able to maintain
separate timer for each display.

Bug: 188838426
Test: check idle timer is still working for both kernel idle timer and
      SF idle timer
Change-Id: If0bd6c9a1ba7e204160e722edc6aedaaeef84997
diff --git a/services/surfaceflinger/tests/unittests/TestableScheduler.h b/services/surfaceflinger/tests/unittests/TestableScheduler.h
index a99dabe..1d21bd4 100644
--- a/services/surfaceflinger/tests/unittests/TestableScheduler.h
+++ b/services/surfaceflinger/tests/unittests/TestableScheduler.h
@@ -44,7 +44,7 @@
                       ISchedulerCallback& callback)
           : Scheduler({std::move(vsyncController), std::move(vsyncTracker), nullptr},
                       refreshRateConfigs, callback, createLayerHistory(),
-                      {.supportKernelTimer = false, .useContentDetection = true}) {}
+                      {.useContentDetection = true}) {}
 
     // Used to inject mock event thread.
     ConnectionHandle createConnection(std::unique_ptr<EventThread> eventThread) {