SF: Remove manual enum stringification

Upgrade to scoped enums where applicable. Pull GameMode from TimeStats
into libgui to plumb it as an enum rather than int32_t.

Bug: 185536303
Test: libsurfaceflinger_unittest
Change-Id: I81fdd24805757ef953484055ee867684eb94fecf
diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 861d496..490775f 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -401,12 +401,13 @@
         const Fps refreshRate = display->refreshRateConfigs().getCurrentRefreshRate().getFps();
         const std::optional<Fps> renderRate =
                 mFlinger->mScheduler->getFrameRateOverride(getOwnerUid());
+
+        const auto vote = frameRateToSetFrameRateVotePayload(mDrawingState.frameRate);
+        const auto gameMode = getGameMode();
+
         if (presentFence->isValid()) {
             mFlinger->mTimeStats->setPresentFence(layerId, mCurrentFrameNumber, presentFence,
-                                                  refreshRate, renderRate,
-                                                  frameRateToSetFrameRateVotePayload(
-                                                          mDrawingState.frameRate),
-                                                  getGameMode());
+                                                  refreshRate, renderRate, vote, gameMode);
             mFlinger->mFrameTracer->traceFence(layerId, getCurrentBufferId(), mCurrentFrameNumber,
                                                presentFence,
                                                FrameTracer::FrameEvent::PRESENT_FENCE);
@@ -417,10 +418,7 @@
             // timestamp instead.
             const nsecs_t actualPresentTime = display->getRefreshTimestamp();
             mFlinger->mTimeStats->setPresentTime(layerId, mCurrentFrameNumber, actualPresentTime,
-                                                 refreshRate, renderRate,
-                                                 frameRateToSetFrameRateVotePayload(
-                                                         mDrawingState.frameRate),
-                                                 getGameMode());
+                                                 refreshRate, renderRate, vote, gameMode);
             mFlinger->mFrameTracer->traceTimestamp(layerId, getCurrentBufferId(),
                                                    mCurrentFrameNumber, actualPresentTime,
                                                    FrameTracer::FrameEvent::PRESENT_FENCE);