Remove event thread connection metric.

It's not an actionable metric and is causing performance problems due to
lock contention. So, remove the code.

Bug: 170661858
Test: builds
Change-Id: I70fc2772d2cfa1c8364775427b1e8f08ce4ca0ff
diff --git a/services/surfaceflinger/TimeStats/TimeStats.cpp b/services/surfaceflinger/TimeStats/TimeStats.cpp
index 630cef1..368cb41 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.cpp
+++ b/services/surfaceflinger/TimeStats/TimeStats.cpp
@@ -106,7 +106,8 @@
         atom->set_client_composition_frames(mTimeStats.clientCompositionFramesLegacy);
         atom->set_display_on_millis(mTimeStats.displayOnTimeLegacy);
         atom->set_animation_millis(mTimeStats.presentToPresentLegacy.totalTime());
-        atom->set_event_connection_count(mTimeStats.displayEventConnectionsCountLegacy);
+        // Deprecated
+        atom->set_event_connection_count(0);
         *atom->mutable_frame_duration() =
                 histogramToProto(mTimeStats.frameDurationLegacy.hist, mMaxPulledHistogramBuckets);
         *atom->mutable_render_engine_timing() =
@@ -356,16 +357,6 @@
     mTimeStats.refreshRateSwitchesLegacy++;
 }
 
-void TimeStats::recordDisplayEventConnectionCount(int32_t count) {
-    if (!mEnabled.load()) return;
-
-    ATRACE_CALL();
-
-    std::lock_guard<std::mutex> lock(mMutex);
-    mTimeStats.displayEventConnectionsCountLegacy =
-            std::max(mTimeStats.displayEventConnectionsCountLegacy, count);
-}
-
 static int32_t toMs(nsecs_t nanos) {
     int64_t millis =
             std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::nanoseconds(nanos))
@@ -1072,7 +1063,6 @@
     mTimeStats.compositionStrategyPredictedLegacy = 0;
     mTimeStats.compositionStrategyPredictionSucceededLegacy = 0;
     mTimeStats.refreshRateSwitchesLegacy = 0;
-    mTimeStats.displayEventConnectionsCountLegacy = 0;
     mTimeStats.displayOnTimeLegacy = 0;
     mTimeStats.presentToPresentLegacy.hist.clear();
     mTimeStats.frameDurationLegacy.hist.clear();