Add new metrics for baseline profile measurement

Added custom metrics to better understand how effecetive a baseline
profile is. These TraceSectionMetrics keep track of JIT compilations
as well as class initializations which should go down when a BP is
properly applied to the app.

Change-Id: Idd1044bdccc3cbaf64aba8d7a909c4d150f82341

benchmarks/src/main/kotlin/com/google/samples/apps/nowinandroid/BaselineProfileMetrics.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.samples.apps.nowinandroid
+
+import androidx.benchmark.macro.ExperimentalMetricApi
+import androidx.benchmark.macro.StartupTimingMetric
+import androidx.benchmark.macro.TraceSectionMetric
+
+/**
+ * Custom Metrics to measure baseline profile effectiveness.
+ */
+class BaselineProfileMetrics {
+    companion object {
+        /**
+         * A [TraceSectionMetric] that tracks the time spent in JIT compilation.
+         *
+         * This number should go down when a baseline profile is applied properly.
+         */
+        @OptIn(ExperimentalMetricApi::class)
+        val jitCompilationMetric = TraceSectionMetric("JIT Compiling %", label = "JIT compilation")
+
+        /**
+         * A [TraceSectionMetric] that tracks the time spent in class initialization.
+         *
+         * This number should go down when a baseline profile is applied properly.
+         */
+        @OptIn(ExperimentalMetricApi::class)
+        val classInitMetric = TraceSectionMetric("L%/%;", label = "ClassInit")
+
+        /**
+         * Metrics relevant to startup and baseline profile effectiveness measurement.
+         */
+        @OptIn(ExperimentalMetricApi::class)
+        val allMetrics = listOf(StartupTimingMetric(), jitCompilationMetric, classInitMetric)
+    }
+}

benchmarks/src/main/kotlin/com/google/samples/apps/nowinandroid/startup/StartupBenchmark.kt

@@ -20,9 +20,9 @@ import androidx.benchmark.macro.BaselineProfileMode.Disable
 import androidx.benchmark.macro.BaselineProfileMode.Require
 import androidx.benchmark.macro.CompilationMode
 import androidx.benchmark.macro.StartupMode.COLD
-import androidx.benchmark.macro.StartupTimingMetric
 import androidx.benchmark.macro.junit4.MacrobenchmarkRule
 import androidx.test.internal.runner.junit4.AndroidJUnit4ClassRunner
+import com.google.samples.apps.nowinandroid.BaselineProfileMetrics
 import com.google.samples.apps.nowinandroid.PACKAGE_NAME
 import com.google.samples.apps.nowinandroid.allowNotifications
 import com.google.samples.apps.nowinandroid.foryou.forYouWaitForContent
@@ -58,7 +58,7 @@ class StartupBenchmark {
 
     private fun startup(compilationMode: CompilationMode) = benchmarkRule.measureRepeated(
         packageName = PACKAGE_NAME,
-        metrics = listOf(StartupTimingMetric()),
+        metrics = BaselineProfileMetrics.allMetrics,
         compilationMode = compilationMode,
         // More iterations result in higher statistical significance.
         iterations = 20,