Change WebRTC IP handling policy from multiple booleans to an enum.

chrome/common/extensions/api/privacy.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": "privacy",
     "description": "Use the <code>chrome.privacy</code> API to control usage of the features in Chrome that can affect a user's privacy. This API relies on the <a href='types#ChromeSetting'>ChromeSetting prototype of the type API</a> for getting and setting Chrome's configuration.",
+    "types": [
+      {
+        "id": "IPHandlingPolicy",
+        "type": "string",
+        "enum": ["default", "default_public_interface_only", "disable_non_proxied_udp"],
+        "description": "The IP handling policy of WebRTC."
+      }
+    ],
     "properties": {
       "network": {
         "type": "object",
         "value": {},
         "description": "Settings that influence Chrome's handling of network connections in general.",
         "properties": {
           "networkPredictionEnabled": {
             "$ref": "types.ChromeSetting",
             "value": ["networkPredictionEnabled", {"type":"boolean"}],
             "description": "If enabled, Chrome attempts to speed up your web browsing experience by pre-resolving DNS entries, prerendering sites (<code>&lt;link rel='prefetch' ...&gt;</code>), and preemptively opening TCP and SSL connections to servers.  This preference's value is a boolean, defaulting to <code>true</code>."
           },
           "webRTCMultipleRoutesEnabled": {
             "$ref": "types.ChromeSetting",
             "value": ["webRTCMultipleRoutesEnabled", {"type":"boolean"}],
+            "deprecated": "Please use $(ref:privacy.webRTCIPHandlingPolicy). This remains read-only for backward compatibility in this release and will be removed in the future.",

[Devlin, 2015/10/27 20:45:44]

webRTCIPHandlingPolicy isn't defined on privacy, it's defined on
privacy.network.  You could try $(ref:privacy.network.webRTCIPHandlingPolicy),
which would hopefully work.

[guoweis_left_chromium, 2015/10/28 16:39:51]

That was the first thing I ever tried. No, it didn't do the trick... Still
warning.

[Devlin, 2015/10/28 22:39:37]

Dang.  I guess we don't parse properties for cross-references.  In lieu of that,
pick one between just typing it out or linking to the type (IPHandlingPolicy).

             "description": "If enabled, Chrome will explore all possible routing options when using WebRTC to find the most performant path, possibly exposing user's private IP address. Otherwise, WebRTC traffic will be routed the same way as regular HTTP. This preference's value is a boolean, defaulting to <code>true</code>."
           },
           "webRTCNonProxiedUdpEnabled": {
             "$ref": "types.ChromeSetting",
             "value": ["webRTCNonProxiedUdpEnabled", {"type":"boolean"}],
+            "deprecated": "Please use $(ref:privacy.webRTCIPHandlingPolicy). This remains read-only for backward compatibility in this release and will be removed in the future.",

[Devlin, 2015/10/27 20:45:44]

It's not read-only, right?

[guoweis_left_chromium, 2015/10/28 16:39:51]

Done.

             "description": "If enabled, Chrome is allowed to use non-proxied UDP to connect to peers or TURN servers when using WebRTC. Since most proxy servers don't handle UDP, using UDP possibly exposes user's IP address. Turning this off effectively forces WebRTC to only use TCP for now, until UDP proxy support is available in Chrome and such proxies are widely deployed. As a result, it also might hurt media performance and increase the load for proxy servers. This preference's value is a boolean, defaulting to <code>true</code>."
+          },
+          "webRTCIPHandlingPolicy": {
+            "$ref": "types.ChromeSetting",
+            "value": ["webRTCIPHandlingPolicy", {"$ref":"IPHandlingPolicy"}],
+             "description": "Allow users to specify the media performance/privacy tradeoffs which impacts how WebRTC traffic will be routed and how much local address information is exposed. This preference's value is of type IPHandlingPolicy, defaulting to <code>default</code>."
           }
         }
       },
       "services": {
         "type": "object",
         "value": {},
         "description": "Settings that enable or disable features that require third-party network services provided by Google and your default search provider.",
         "properties": {
           "alternateErrorPagesEnabled": {
             "$ref": "types.ChromeSetting",
@@ skipping 66 matching lines @@
             "$ref": "types.ChromeSetting",
             "value": ["protectedContentEnabled", {"type":"boolean"}],
             "description": "<strong>Available on Windows and ChromeOS only</strong>: If enabled, Chrome provides a unique ID to plugins in order to run protected content. The value of this preference is of type boolean, and the default value is <code>true</code>.",
             "platforms": ["windows", "cros", "cros touch"]
           }
         }
       }
     }
   }
 ]