Use the externally_connectable schema from manifest_types.json to generate its

chrome/common/extensions/docs/static/css/api.css

Index: chrome/common/extensions/docs/static/css/api.css
diff --git a/chrome/common/extensions/docs/static/css/api.css b/chrome/common/extensions/docs/static/css/api.css
deleted file mode 100644
index 58175fa83c5c4f8d2469fde3a7d0cfcbceabdf9b..0000000000000000000000000000000000000000
--- a/chrome/common/extensions/docs/static/css/api.css
+++ /dev/null
@@ -1,42 +0,0 @@
-/* Copyright (c) 2012 The Chromium Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-.type_name,
-.variable,
-.property {
-  font-style: italic;
-}
-
-.api_reference div.summary {
-  border: 1px solid #93B4D9;
-  font-family: "Courier New", courier, monospace;
-  padding: 0.5em 0.5em 0.5em 2em;
-  text-indent: -1.5em;
-  background-color: #CADEF4;
-  margin-top: 1em;
-}
-
-/* This style is used because types with functions prefix the function with the
- * type name, using a lowercase first letter.
- */
-.api_reference .uncapitalize:first-letter {
-  text-transform: lowercase;
-}
-
-.api_reference .capitalize:first-letter {
-  text-transform: uppercase;
-}
-
-.api_reference div.description {
-  margin-left: 2em;
-}
-
-div.summary .subdued {
-  color: #7594B8;
-}
-
-.optional {
-  color: #7D7D7D;
-}