Prepare 2.3.0-pre.1 release

Author: justinfagnani

CHANGELOG.md

@@ -16,7 +16,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 <!-- ### Removed -->
 <!-- ### Fixed -->
 
-## Unreleased
+## [2.3.0-pre.1] - 2020-03-17
 
 ### Changed
 * Added a static `getPropertyDescriptor` method to allow easier customization of property accessors. This method should return a a `PropertyDescriptor` to install on the property. If no descriptor is returned, a property accessor is not be created. ([#911](https://github.com/Polymer/lit-element/issues/911))

package.json

@@ -1,6 +1,6 @@
 {
   "name": "lit-element",
-  "version": "2.2.1",
+  "version": "2.3.0-pre.1",
   "description": "A simple base class for creating fast, lightweight web components",
   "license": "BSD-3-Clause",
   "homepage": "https://lit-element.polymer-project.org/",

src/lit-element.ts

@@ -31,7 +31,7 @@ declare global {
 // This line will be used in regexes to search for LitElement usage.
 // TODO(justinfagnani): inject version number at build time
 (window['litElementVersions'] || (window['litElementVersions'] = []))
-    .push('2.2.1');
+    .push('2.3.0-pre.1');
 
 export interface CSSResultArray extends Array<CSSResult|CSSResultArray> {}