Revert "SF: Remove refresh_rate_switching flag."

This reverts commit 8c6f3f6bd0c5edce7aa9bfd61b64dd2e7dc43deb.

Reason for revert: Crashes on ToT (b/148822765, b/148821456)

Change-Id: If1bc13b33321727244c3b0f15a0e7b30665d1c43
diff --git a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
index be233bb..2491533 100644
--- a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
+++ b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
@@ -203,7 +203,8 @@
         std::vector<scheduler::RefreshRateConfigs::InputConfig> configs{
                 {{HwcConfigIndexType(0), HwcConfigGroupType(0), 16666667}}};
         mFlinger->mRefreshRateConfigs = std::make_unique<
-                scheduler::RefreshRateConfigs>(configs, /*currentConfig=*/HwcConfigIndexType(0));
+                scheduler::RefreshRateConfigs>(/*refreshRateSwitching=*/false, configs,
+                                               /*currentConfig=*/HwcConfigIndexType(0));
         mFlinger->mRefreshRateStats = std::make_unique<
                 scheduler::RefreshRateStats>(*mFlinger->mRefreshRateConfigs, *mFlinger->mTimeStats,
                                              /*currentConfig=*/HwcConfigIndexType(0),