[url_launcher] Publish fully federated version (#4536)

Restores the app-facing package to a publishable state now that _android
and _ios implementation packages are published.

Part of flutter/flutter#68498
diff --git a/packages/url_launcher/url_launcher/CHANGELOG.md b/packages/url_launcher/url_launcher/CHANGELOG.md
index a7feb11..46b71f6 100644
--- a/packages/url_launcher/url_launcher/CHANGELOG.md
+++ b/packages/url_launcher/url_launcher/CHANGELOG.md
@@ -1,4 +1,4 @@
-## NEXT
+## 6.0.16
 
 * Moves Android and iOS implementations to federated packages.
 
diff --git a/packages/url_launcher/url_launcher/pubspec.yaml b/packages/url_launcher/url_launcher/pubspec.yaml
index 48cf5d2..5844031 100644
--- a/packages/url_launcher/url_launcher/pubspec.yaml
+++ b/packages/url_launcher/url_launcher/pubspec.yaml
@@ -3,10 +3,7 @@
   web, phone, SMS, and email schemes.
 repository: https://github.com/flutter/plugins/tree/master/packages/url_launcher/url_launcher
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+url_launcher%22
-version: 6.0.15
-# Temporarily disable publishing to allow moving Android and iOS
-# implementations.
-publish_to: none
+version: 6.0.16
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
@@ -32,11 +29,8 @@
   flutter:
     sdk: flutter
   meta: ^1.3.0
-  # Temporary path dependencies to allow moving Android and iOS implementations.
-  url_launcher_android:
-    path: ../url_launcher_android
-  url_launcher_ios:
-    path: ../url_launcher_ios
+  url_launcher_android: ^6.0.13
+  url_launcher_ios: ^6.0.13
   url_launcher_linux: ^2.0.0
   url_launcher_macos: ^2.0.0
   url_launcher_platform_interface: ^2.0.3