revert removing builtin extensions from dev html

src/vs/code/browser/workbench/workbench-dev.html

@@ -10,6 +10,9 @@
 		<!-- Workbench Configuration -->
 		<meta id="vscode-workbench-web-configuration" data-settings="{{WORKBENCH_WEB_CONFIGURATION}}">
 
+		<!-- Builtin Extensions (running out of sources) -->
+		<meta id="vscode-workbench-builtin-extensions" data-settings="{{WORKBENCH_BUILTIN_EXTENSIONS}}">
+
 		<!-- Workarounds/Hacks (remote user data uri) -->
 		<meta id="vscode-remote-user-data-uri" data-settings="{{REMOTE_USER_DATA_URI}}">