For #18594: Highlight the "Default browser" system setting on Android >= N

Although not public APIs we can use specific extras in the Intent used to open
system settings such that the "Default browser" setting is highlighted to
provide a better UX for users looking to set Fenix as default.

app/src/main/java/org/mozilla/fenix/home/intent/DeepLinkIntentProcessor.kt

@@ -10,6 +10,7 @@ import android.net.Uri
 import android.os.Build
 import android.os.Build.VERSION.SDK_INT
 import android.provider.Settings
+import androidx.core.os.bundleOf
 import androidx.navigation.NavController
 import mozilla.components.concept.engine.EngineSession
 import mozilla.components.support.base.log.logger.Logger
@@ -88,6 +89,9 @@ class DeepLinkIntentProcessor(
             "make_default_browser" -> {
                 if (SDK_INT >= Build.VERSION_CODES.N) {
                     val settingsIntent = Intent(Settings.ACTION_MANAGE_DEFAULT_APPS_SETTINGS)
+                    settingsIntent.putExtra(SETTINGS_SELECT_OPTION_KEY, DEFAULT_BROWSER_APP_OPTION)
+                    settingsIntent.putExtra(SETTINGS_SHOW_FRAGMENT_ARGS,
+                        bundleOf(SETTINGS_SELECT_OPTION_KEY to DEFAULT_BROWSER_APP_OPTION))
                     activity.startActivity(settingsIntent)
                 }
             }
@@ -150,4 +154,10 @@ class DeepLinkIntentProcessor(
          */
         fun verifyDeepLink(deepLink: Uri): Boolean
     }
+
+    companion object {
+        private const val SETTINGS_SELECT_OPTION_KEY = ":settings:fragment_args_key"
+        private const val SETTINGS_SHOW_FRAGMENT_ARGS = ":settings:show_fragment_args"
+        private const val DEFAULT_BROWSER_APP_OPTION = "default_browser"
+    }
 }

app/src/main/java/org/mozilla/fenix/settings/SettingsFragment.kt

@@ -19,6 +19,7 @@ import android.view.LayoutInflater
 import android.widget.Toast
 import androidx.annotation.VisibleForTesting
 import androidx.appcompat.app.AlertDialog
+import androidx.core.os.bundleOf
 import androidx.lifecycle.lifecycleScope
 import androidx.navigation.NavDirections
 import androidx.navigation.findNavController
@@ -501,6 +502,9 @@ class SettingsFragment : PreferenceFragmentCompat() {
     private fun navigateUserToDefaultAppsSettings() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
             val intent = Intent(android.provider.Settings.ACTION_MANAGE_DEFAULT_APPS_SETTINGS)
+            intent.putExtra(SETTINGS_SELECT_OPTION_KEY, DEFAULT_BROWSER_APP_OPTION)
+            intent.putExtra(SETTINGS_SHOW_FRAGMENT_ARGS,
+                bundleOf(SETTINGS_SELECT_OPTION_KEY to DEFAULT_BROWSER_APP_OPTION))
             startActivity(intent)
         }
     }
@@ -572,5 +576,8 @@ class SettingsFragment : PreferenceFragmentCompat() {
         private const val SCROLL_INDICATOR_DELAY = 10L
         private const val FXA_SYNC_OVERRIDE_EXIT_DELAY = 2000L
         private const val AMO_COLLECTION_OVERRIDE_EXIT_DELAY = 3000L
+        private const val SETTINGS_SELECT_OPTION_KEY = ":settings:fragment_args_key"
+        private const val SETTINGS_SHOW_FRAGMENT_ARGS = ":settings:show_fragment_args"
+        private const val DEFAULT_BROWSER_APP_OPTION = "default_browser"
     }
 }