Merge "Trace callbacks for user switcher" into main

import android.util.Log

import androidx.annotation.GuardedBy

import androidx.annotation.WorkerThread

import com.android.app.tracing.coroutines.launchTraced as launch

import com.android.app.tracing.traceSection

import com.android.systemui.Dumpable

import com.android.systemui.dump.DumpManager

import com.android.systemui.flags.FeatureFlagsClassic

import kotlinx.coroutines.asCoroutineDispatcher

import kotlinx.coroutines.coroutineScope

import kotlinx.coroutines.delay

import com.android.app.tracing.coroutines.launchTraced as launch

import kotlinx.coroutines.sync.Mutex

/**

        list.forEach {

            val callback = it.callback.get()

            if (callback != null) {

                it.executor.execute { action(callback) { latch.countDown() } }

                it.executor.execute {

                    traceSection({ "$callback" }) { action(callback) { latch.countDown() } }

                }

            } else {

                latch.countDown()

            }