SurfaceFlinger: fix SFFakeHWC_test

Few small fixes to make the test pass.

Fixes: 147250281
Test: adb shell data/nativetest64/sffakehwc_test/sffakehwc_test
Change-Id: I1e2ef20adcdd10a78b621eb1bea21a2d30c22afe
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 6d18922..b9c9525 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -5600,11 +5600,10 @@
             repaintEverythingForHWC();
         }
 
-        auto configId = HwcConfigIndexType(defaultConfig);
-        display->setActiveConfig(configId);
+        display->setActiveConfig(defaultConfig);
         const nsecs_t vsyncPeriod =
-                mRefreshRateConfigs->getRefreshRateFromConfigId(configId).vsyncPeriod;
-        mScheduler->onConfigChanged(mAppConnectionHandle, display->getId()->value, configId,
+                getHwComposer().getConfigs(*displayId)[defaultConfig.value()]->getVsyncPeriod();
+        mScheduler->onConfigChanged(mAppConnectionHandle, display->getId()->value, defaultConfig,
                                     vsyncPeriod);
         return NO_ERROR;
     }