Perform Fennec data migration within fennecProduction

app/build.gradle

@@ -393,6 +393,9 @@ dependencies {
     implementation Deps.mozilla_support_rustlog
     implementation Deps.mozilla_support_utils
 
+    // We only care about support-migration in builds that will be overwriting Fennec.
+    fennecProductionImplementation Deps.mozilla_support_migration
+
     implementation Deps.mozilla_ui_colors
     implementation Deps.mozilla_ui_icons
     implementation Deps.mozilla_ui_publicsuffixlist

app/src/fennecProduction/AndroidManifest.xml

@@ -7,6 +7,11 @@
                 - https://issuetracker.google.com/issues/36905922
 -->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-      android:sharedUserId="${sharedUserId}">
+    xmlns:tools="http://schemas.android.com/tools"
+    android:sharedUserId="${sharedUserId}">
+    <application
+        android:name="org.mozilla.fenix.MigratingFenixApplication"
+        tools:replace="android:name">
+    </application>
 </manifest>
 

app/src/fennecProduction/java/org/mozilla/fenix/MigratingFenixApplication.kt

@@ -0,0 +1,34 @@
+/* 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
+
+import mozilla.components.support.ktx.android.content.isMainProcess
+import mozilla.components.support.migration.FennecMigrator
+
+/**
+ * An application class which knows how to migrate Fennec data.
+ */
+class MigratingFenixApplication : FenixApplication() {
+    override fun setupApplication() {
+        super.setupApplication()
+
+        // Same check as is present in super.setupApplication:
+        if (!isMainProcess()) {
+            // If this is not the main process then do not continue with the migration here.
+            // Migration only needs to be done in our app's main process and should not be done in other processes like
+            // a GeckoView child process or the crash handling process. Most importantly we never want to end up in a
+            // situation where we create a GeckoRuntime from the Gecko child process.
+            return
+        }
+
+        val migrator = FennecMigrator.Builder(this)
+            .migrateOpenTabs(this.components.core.sessionManager)
+            .migrateHistory(this.components.core.historyStorage)
+            .migrateBookmarks(this.components.core.bookmarksStorage)
+            .build()
+
+        migrator.migrateAsync()
+    }
+}

buildSrc/src/main/java/Dependencies.kt

@@ -42,7 +42,7 @@ object Versions {
     // that we depend on directly for the fenix-megazord (and for it's
     // forUnitTest variant), and it's important that it be kept in
     // sync with the version used by android-components above.
-    const val mozilla_appservices = "0.41.0"
+    const val mozilla_appservices = "0.42.0"
 
     const val autodispose = "1.1.0"
     const val adjust = "4.11.4"
@@ -153,6 +153,7 @@ object Deps {
     const val mozilla_support_rustlog = "org.mozilla.components:support-rustlog:${Versions.mozilla_android_components}"
     const val mozilla_support_utils = "org.mozilla.components:support-utils:${Versions.mozilla_android_components}"
     const val mozilla_support_test = "org.mozilla.components:support-test:${Versions.mozilla_android_components}"
+    const val mozilla_support_migration = "org.mozilla.components:support-migration:${Versions.mozilla_android_components}"
 
     const val sentry = "io.sentry:sentry-android:${Versions.sentry}"
     const val leakcanary = "com.squareup.leakcanary:leakcanary-android:${Versions.leakcanary}"