For #17816: add profiler marker for 2x Activity.onCreate.

The IntentReceiverActivity one is particularly useful to quickly determine
when we can begin executing code in the WARM VIEW case (i.e. "Set selection
begin here").

The HomeActivity one is useful for COLD start up analysis in similar
ways and to see the Activity transitions in WARM VIEW.

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

@@ -163,6 +163,9 @@ open class HomeActivity : LocaleAwareAppCompatActivity(), NavHostActivity {
     private lateinit var navigationToolbar: Toolbar
 
     final override fun onCreate(savedInstanceState: Bundle?) {
+        // DO NOT MOVE ANYTHING ABOVE THIS addMarker CALL.
+        components.core.engine.profiler?.addMarker("Activity.onCreate", "HomeActivity")
+
         components.strictMode.attachListenerToDisablePenaltyDeath(supportFragmentManager)
         // There is disk read violations on some devices such as samsung and pixel for android 9/10
         components.strictMode.resetAfter(StrictMode.allowThreadDiskReads()) {

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

@@ -26,6 +26,9 @@ class IntentReceiverActivity : Activity() {
 
     @VisibleForTesting
     override fun onCreate(savedInstanceState: Bundle?) {
+        // DO NOT MOVE ANYTHING ABOVE THIS addMarker CALL.
+        components.core.engine.profiler?.addMarker("Activity.onCreate", "IntentReceiverActivity")
+
         // StrictMode violation on certain devices such as Samsung
         components.strictMode.resetAfter(StrictMode.allowThreadDiskReads()) {
             super.onCreate(savedInstanceState)