For #22054: add marker for root view layout/measure.

The onLayout marker may be redundant to onGlobalLayout marker but I'm not
sure yet so let's leave them both in and observe if that's the case.

Here's a profile with the markers: https://share.firefox.dev/3lZaOQb

app/src/main/java/org/mozilla/fenix/HomeActivity.kt

@@ -211,6 +211,7 @@ open class HomeActivity : LocaleAwareAppCompatActivity(), NavHostActivity {
 
         binding = ActivityHomeBinding.inflate(layoutInflater)
         setContentView(binding.root)
+        binding.root.profilerProvider = { components.core.engine.profiler }
         ProfilerMarkers.addListenerForOnGlobalLayout(components.core.engine, this, binding.root)
 
         // Must be after we set the content view

app/src/main/java/org/mozilla/fenix/perf/RootLinearLayout.kt

@@ -0,0 +1,33 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.fenix.perf
+
+import android.content.Context
+import android.util.AttributeSet
+import android.widget.LinearLayout
+import mozilla.components.concept.base.profiler.Profiler
+
+private const val DETAIL_TEXT = "RootLinearLayout"
+
+/**
+ * A [LinearLayout] that adds profiler markers for various methods. This is intended to be used on
+ * the root view of the view hierarchy to understand global measure/layout events.
+ */
+class RootLinearLayout(context: Context, attrs: AttributeSet) : LinearLayout(context, attrs) {
+
+    var profilerProvider: () -> Profiler? = { null }
+
+    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
+        val profilerStartTime = profilerProvider.invoke()?.getProfilerTime()
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
+        profilerProvider.invoke()?.addMarker("onMeasure", profilerStartTime, DETAIL_TEXT)
+    }
+
+    override fun onLayout(changed: Boolean, l: Int, t: Int, r: Int, b: Int) {
+        val profilerStartTime = profilerProvider.invoke()?.getProfilerTime()
+        super.onLayout(changed, l, t, r, b)
+        profilerProvider.invoke()?.addMarker("onLayout", profilerStartTime, DETAIL_TEXT)
+    }
+}

app/src/main/res/layout/activity_home.xml

@@ -1,7 +1,8 @@
 <!-- This Source Code Form is subject to the terms of the Mozilla Public
    - License, v. 2.0. If a copy of the MPL was not distributed with this
    - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<org.mozilla.fenix.perf.RootLinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -24,4 +25,4 @@
         android:layout_height="match_parent"
         app:defaultNavHost="true"
         app:navGraph="@navigation/nav_graph" />
-</LinearLayout>
+</org.mozilla.fenix.perf.RootLinearLayout>