Closes 20975: Run metadata cleanup after Megazord.init()

This ensures that we do not attempt places initialization before
Megazord.init() finishes, and that touching BrowserStore does not
kick-off places initialization (due to the `cleanup` call being a
side-effect of creating metadata middleware, used as part of the
BrowserStore).

Glean initialization happens before initialize megazord, and it touches
core.store BrowserStore instance, kicking-off places initialization on
an IO thread (due to the cleanup call), which raced megazord
initialization on the main thread.

App init sequence is a bit of a mine-field, so this patch takes the easy
way out and doesn't attempt to re-order initialization sequence. Also,
initializing places as a side-effect of touching BrowserStore was also,
clearly, a bug.

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

@@ -72,6 +72,7 @@ import org.mozilla.fenix.GleanMetrics.Addons
 import org.mozilla.fenix.GleanMetrics.AndroidAutofill
 import org.mozilla.fenix.GleanMetrics.Preferences
 import org.mozilla.fenix.GleanMetrics.SearchDefaultEngine
+import org.mozilla.fenix.components.Core
 import org.mozilla.fenix.components.metrics.Event
 import org.mozilla.fenix.components.metrics.MozillaProductDetector
 import org.mozilla.fenix.components.toolbar.ToolbarPosition
@@ -241,6 +242,14 @@ open class FenixApplication : LocaleAwareApplication(), Provider {
                         components.core.bookmarksStorage.warmUp()
                         components.core.passwordsStorage.warmUp()
                         components.core.autofillStorage.warmUp()
+
+                        // This service uses `historyStorage`, and so we can only touch it when we know
+                        // it's safe to touch `historyStorage. By 'safe', we mainly mean that underlying
+                        // places library will be able to load, which requires first running Megazord.init().
+                        // The visual completeness tasks are scheduled after the Megazord.init() call.
+                        components.core.historyMetadataService.cleanup(
+                            System.currentTimeMillis() - Core.HISTORY_METADATA_MAX_AGE_IN_MS
+                        )
                     }
 
                     SecurePrefsTelemetry(this@FenixApplication, components.analytics.experiments).startTests()

app/src/main/java/org/mozilla/fenix/components/Core.kt

@@ -254,9 +254,7 @@ class Core(
      * The [HistoryMetadataService] is used to record history metadata.
      */
     val historyMetadataService: HistoryMetadataService by lazyMonitored {
-        DefaultHistoryMetadataService(storage = historyStorage).apply {
-            cleanup(System.currentTimeMillis() - HISTORY_METADATA_MAX_AGE_IN_MS)
-        }
+        DefaultHistoryMetadataService(storage = historyStorage)
     }
 
     /**
@@ -454,6 +452,6 @@ class Core(
         private const val KEY_STORAGE_NAME = "core_prefs"
         private const val PASSWORDS_KEY = "passwords"
         private const val RECENTLY_CLOSED_MAX = 10
-        private const val HISTORY_METADATA_MAX_AGE_IN_MS = 14 * 24 * 60 * 60 * 1000 // 14 days
+        const val HISTORY_METADATA_MAX_AGE_IN_MS = 14 * 24 * 60 * 60 * 1000 // 14 days
     }
 }