Add `chrome.contentSettings.location`.

chrome/common/extensions/api/content_settings.json

 // 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.
 
 [
   {
     "namespace": "contentSettings",
     "description": "Use the <code>chrome.contentSettings</code> API to change settings that control whether websites can use features such as cookies, JavaScript, and plug-ins. More generally speaking, content settings allow you to customize Chrome's behavior on a per-site basis instead of globally.",
     "compiler_options": {
       "generate_type_functions": true
@@ skipping 179 matching lines @@
         ]
       },
       "javascript": {
         "$ref": "ContentSetting",
         "description": "Whether to run JavaScript. One of<br><var>allow</var>: Run JavaScript,<br><var>block</var>: Don't run JavaScript. <br>Default is <var>allow</var>.<br>The primary URL is the main-frame URL. The secondary URL is not used.",
         "value": [
           "javascript",
           {"type":"string", "enum": ["allow", "block"]}
         ]
       },
+      "location": {
+        "$ref": "ContentSetting",
+        "description": "Whether to allow Geolocation. One of <br><var>allow</var>: Allow sites to track your physical location,<br><var>block</var>: Don't allow sites to track your physical location,<br><var>ask</var>: Ask before allowing sites to track your physical location. <br>Default is <var>ask</var>.<br>The primary URL is the main-frame URL. The secondary URL is not used.",

[Bernhard Bauer, 2015/01/12 14:35:58]

I think the primary URL is the requesting iframe, the secondary URL is the
embedding iframe (i.e. main frame).

+        "value": [
+          "location",
+          {"type":"string", "enum": ["allow", "block", "ask"]}
+        ]
+      },
       "plugins": {
         "$ref": "ContentSetting",
         "description": "Whether to run plug-ins. One of<br><var>allow</var>: Run plug-ins automatically,<br><var>block</var>: Don't run plug-ins automatically. <br>Default is <var>allow</var>.<br>The primary URL is the main-frame URL. The secondary URL is not used.",
         "value": [
           "plugins",
           {"type":"string", "enum": ["allow", "block"]}
         ]
       },
       "popups": {
         "$ref": "ContentSetting",
         "description": "Whether to allow sites to show pop-ups. One of<br><var>allow</var>: Allow sites to show pop-ups,<br><var>block</var>: Don't allow sites to show pop-ups. <br>Default is <var>block</var>.<br>The primary URL is the main-frame URL. The secondary URL is not used.",
         "value": [
           "popups",
           {"type":"string", "enum": ["allow", "block"]}
         ]
       },
       "notifications": {
         "$ref": "ContentSetting",
         "description": "Whether to allow sites to show desktop notifications. One of<br><var>allow</var>: Allow sites to show desktop notifications,<br><var>block</var>: Don't allow sites to show desktop notifications,<br><var>ask</var>: Ask when a site wants to show desktop notifications. <br>Default is <var>ask</var>.<br>The primary URL is the main-frame URL. The secondary URL is not used.",
         "value": [
           "notifications",
           {"type":"string", "enum": ["allow", "block", "ask"]}
         ]
       }
     }
   }
 ]