Remove PowerMode from RefreshRateStats

This is always called with PowerMode::OFF, so simplify the constructor.
No change in logical behavior.

Bug: 316575264
Test: mmma -j frameworks/native/services/surfaceflinger
Change-Id: Id2ed54b896d41888aa4c4526fc7000243b764d1b
diff --git a/services/surfaceflinger/tests/unittests/RefreshRateStatsTest.cpp b/services/surfaceflinger/tests/unittests/RefreshRateStatsTest.cpp
index e2e3d7b..fba77e9 100644
--- a/services/surfaceflinger/tests/unittests/RefreshRateStatsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/RefreshRateStatsTest.cpp
@@ -37,7 +37,7 @@
     ~RefreshRateStatsTest();
 
     void resetStats(Fps fps) {
-        mRefreshRateStats = std::make_unique<RefreshRateStats>(mTimeStats, fps, PowerMode::OFF);
+        mRefreshRateStats = std::make_unique<RefreshRateStats>(mTimeStats, fps);
     }
 
     mock::TimeStats mTimeStats;