Prepare to publish (#152)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f56089e..3ab6de0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,4 @@
-## 0.15.0-nullsafety.0-dev
+## 0.15.0-nullsafety.0
 
 - Migrate to null safety.
 - Drop `lastPhase`, `beforeRcDataPhase`, and `container` fields from
diff --git a/pubspec.yaml b/pubspec.yaml
index df0411b..7300645 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,24 +1,17 @@
 name: html
-version: 0.15.0-nullsafety.0-dev
+version: 0.15.0-nullsafety.0
 
 description: APIs for parsing and manipulating HTML content outside the browser.
 homepage: https://github.com/dart-lang/html
 
-# Ensure package is tested internally and remove -dev from version to publish.
-publish_to: none
-
 environment:
   sdk: ">=2.12.0-0 <3.0.0"
 
 dependencies:
-  csslib: ^0.17.0
+  csslib: ^0.17.0-nullsafety
   source_span: ^1.8.0-nullsafety
 
 dev_dependencies:
   path: ^1.8.0-nullsafety
   pedantic: ^1.10.0-nullsafety
   test: ^1.16.0-nullsafety
-
-dependency_overrides:
-  csslib:
-    git: git://github.com/dart-lang/csslib.git