[Extensions Docs] Remove documentation for chrome_ui_overrides

The chrome_ui_overrides feature allowed developers to override the
native bookmarks UI, but never shipped and has since been removed.
Remove the corresponding documentation.

Bug: 894447
Change-Id: Ie81762ef92ac92b54a834fc2e9621fa737670467
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2130630Reviewed-by: Mike Wittman <wittman@chromium.org>
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755179}

chrome/common/extensions/docs/templates/articles/ui_override.html

-<h1>User Interface Overrides</h1>
-
-<p>
-User interface overrides are a way for extensions to override selected Chrome
-user interface properties.
-</p>
-
-<h2 id="bookmarks">Bookmarks User Interface</h2>
-<p>
-Register the user interface properties you want to override in the
-<a href="manifest">extension manifest</a> like this:
-</p>
-
-<pre>{
-  "name": "My extension",
-  ...
-<b>
-  "chrome_ui_overrides" : {
-    "bookmarks_ui": {
-      "remove_button": "true",
-      "remove_bookmark_shortcut": "true"
-    }
-  }</b>,
-  ...
-}</pre>
-
-<p>
-<ul>
-  <li>
-    <a href="#bookmarks_ui">Bookmark button</a>: the "star" button that is used
-    to bookmark pages. Extensions may remove this button using the settings
-    overrides, and optionally replace it with a browser action or page action.
-  </li>
-
-  <li>
-    <a href="#bookmarks_ui">Bookmark shortcut</a>: the shortcut key that is used
-    to bookmark a page (Ctrl-D on Windows). Extensions may remove this shortcut
-    via the settings overrides, and optionally bind their own command to it
-    using the <code>commands</code> section of the manifest. If the shortcut key
-    is removed or rebound, the corresponding menu item as also removed or
-    overridden respectively.
-  </li>
-</ul>
-</p>
-
-<p class="note">
-<b>Note:</b> Settings overrides for <code>bookmarks_ui</code> are only enabled
-in the Chrome Dev release, and Chrome must be started with the
-<code>--enable-override-bookmarks-ui=1</code> command line flag to enable
-bookmarks user interface overrides.</p>
-
-<h2 id="reference">Reference</h2>
-<p>
-An extension can override one or more of the following properties in the
-manifest:
-</p>
-{{+partials.manifest_type
-  type:apis.extensions.manifestTypes.byName.ChromeUIOverrides /}}

chrome/common/extensions/docs/templates/json/manifest.json

@@ -35,15 +35,6 @@
     "documentation": "settings_override",
     "example": {}
   },
-  "chrome_ui_overrides": {
-    "documentation": "ui_override",
-    "example": {
-      "bookmarks_ui": {
-        "remove_button": true,
-        "remove_bookmark_shortcut": true
-       }
-    }
-  },
   "chrome_url_overrides": {
     "documentation": "override",
     "example": {}

chrome/common/extensions/docs/templates/public/extensions/ui_override.html

-{{+partials.standard_extensions_article article:articles.ui_override/}}