Use HomeFragment's viewLifecycleOwner as the lifecycle for accountMan…

…ager observer registry

If we just use the HomeFragment itself, we end up with a memory leak since the lifecycle events
that would clean up the registry (e.g. destroy) won't run (if the fragment is retained in the backstack, for example).

app/src/main/java/org/mozilla/fenix/home/HomeFragment.kt

@@ -379,11 +379,12 @@ class HomeFragment : Fragment() {
         )
 
         requireComponents.backgroundServices.accountManagerAvailableQueue.runIfReadyOrQueue {
-            // By the time this code runs, we may not be attached to a context.
-            if ((this@HomeFragment).context == null) {
+            // By the time this code runs, we may not be attached to a context or have a view lifecycle owner.
+            if ((this@HomeFragment).view?.context == null) {
                 return@runIfReadyOrQueue
             }
-            requireComponents.backgroundServices.accountManager.register(currentMode, owner = this@HomeFragment)
+
+            requireComponents.backgroundServices.accountManager.register(currentMode, owner = this@HomeFragment.viewLifecycleOwner)
             requireComponents.backgroundServices.accountManager.register(object : AccountObserver {
                 override fun onAuthenticated(account: OAuthAccount, authType: AuthType) {
                     if (authType != AuthType.Existing) {
@@ -398,7 +399,7 @@ class HomeFragment : Fragment() {
                         }
                     }
                 }
-            }, owner = this@HomeFragment)
+            }, owner = this@HomeFragment.viewLifecycleOwner)
         }
 
         if (context.settings().showPrivateModeContextualFeatureRecommender &&
@@ -618,7 +619,7 @@ class HomeFragment : Fragment() {
 
     @SuppressWarnings("ComplexMethod", "LongMethod")
     private fun createHomeMenu(context: Context, menuButtonView: WeakReference<MenuButton>) = HomeMenu(
-        this,
+        this.viewLifecycleOwner,
         context,
         onItemTapped = {
             when (it) {