Avoid calling into HWC in onFirstRef

The information is already available - no need to call into HWC.

This saved around 150-200us per onFirstRef call.

Test: atest UiAutomationTest#testWindowContentFrameStats
Test: PerfTransitionTest
Test: LayerTypeTransactionTest#RefreshRateIsInitialized
Bug: 112352758
Change-Id: I406754d33d53d6c60e354f5a403f1d5568f714c4
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index ee9ee78..d9978b8 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -132,22 +132,7 @@
     CompositorTiming compositorTiming;
     flinger->getCompositorTiming(&compositorTiming);
     mFrameEventHistory.initializeCompositorTiming(compositorTiming);
-}
-
-void Layer::onFirstRef() NO_THREAD_SAFETY_ANALYSIS {
-    if (!isCreatedFromMainThread()) {
-        // Grab the SF state lock during this since it's the only way to safely access HWC
-        mFlinger->mStateLock.lock();
-    }
-
-    const auto& hwc = mFlinger->getHwComposer();
-    const auto& activeConfig = hwc.getActiveConfig(HWC_DISPLAY_PRIMARY);
-    nsecs_t displayPeriod = activeConfig->getVsyncPeriod();
-    mFrameTracker.setDisplayRefreshPeriod(displayPeriod);
-
-    if (!isCreatedFromMainThread()) {
-        mFlinger->mStateLock.unlock();
-    }
+    mFrameTracker.setDisplayRefreshPeriod(compositorTiming.interval);
 }
 
 Layer::~Layer() {