Add a kill switch for all of Web Bluetooth.

content/browser/bluetooth/bluetooth_dispatcher_host.cc

 // Copyright 2014 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.
 
 // ID Not In Map Note:
 // A service, characteristic, or descriptor ID not in the corresponding
 // BluetoothDispatcherHost map [service_to_device_, characteristic_to_service_,
 // descriptor_to_characteristic_] implies a hostile renderer because a renderer
 // obtains the corresponding ID from this class and it will be added to the map
 // at that time.
@@ skipping 1201 matching lines @@
     return;
   }
 
   // The renderer should never send empty filters.
   if (HasEmptyOrInvalidFilter(filters)) {
     bad_message::ReceivedBadMessage(this,
                                     bad_message::BDH_EMPTY_OR_INVALID_FILTERS);
     return;
   }
 
-  if (!GetContentClient()->browser()->AllowWebBluetooth(
-          web_contents->GetBrowserContext(), requesting_origin,
-          embedding_origin)) {
-    RecordRequestDeviceOutcome(
-        UMARequestDeviceOutcome::BLUETOOTH_CHOOSER_GLOBALLY_DISABLED);
-    Send(new BluetoothMsg_RequestDeviceError(
-        thread_id, request_id, WebBluetoothError::ChooserDisabled));
-    return;
+  switch (GetContentClient()->browser()->AllowWebBluetooth(

[ortuno, 2016/03/29 17:48:46]

Doing this so late in OnRequestDeviceImpl seems wrong. I think it would be
better if we did it before we try to initialize the adapter, in OnRequestDevice.

[Jeffrey Yasskin, 2016/03/29 23:13:04]

It probably makes sense to reconsider a lot of the requestDevice ordering, but
it's not intimately tied to adding the kill switch, so let's do it in a separate
patch? We're going to be forced to rearrange some of this anyway when we
refactor it into the PermissionContextBase structure, so let's think about it
then, unless there's some more urgent problem with this ordering.

+      web_contents->GetBrowserContext(), requesting_origin, embedding_origin)) {
+    case ContentBrowserClient::AllowWebBluetoothResult::BLOCK_POLICY: {
+      RecordRequestDeviceOutcome(
+          UMARequestDeviceOutcome::BLUETOOTH_CHOOSER_GLOBALLY_DISABLED);
+      Send(new BluetoothMsg_RequestDeviceError(
+          thread_id, request_id, WebBluetoothError::ChooserDisabled));
+      return;
+    }
+    case ContentBrowserClient::AllowWebBluetoothResult::BLOCK_KILL_SWITCH: {

[ortuno, 2016/03/29 17:48:46]

What do you think about checking if the WebBluetoothFlag is on? That way people
that know what they are doing can still use the feature?

[Jeffrey Yasskin, 2016/03/29 23:13:04]

For now, I think that prevents me from testing this change. I've filed
https://crbug.com/598890 to track this.

+      // Log to the developer console.
+      web_contents->GetMainFrame()->AddMessageToConsole(
+          content::CONSOLE_MESSAGE_LEVEL_LOG,
+          "Bluetooth permission has been blocked.");
+      // Block requests.
+      RecordRequestDeviceOutcome(
+          UMARequestDeviceOutcome::BLUETOOTH_KILL_SWITCH_ENABLED);
+      Send(new BluetoothMsg_RequestDeviceError(
+          thread_id, request_id, WebBluetoothError::KillSwitchEnabled));
+      return;
+    }
+    case ContentBrowserClient::AllowWebBluetoothResult::ALLOW:
+      break;
   }
 
   // Create storage for the information that backs the chooser, and show the
   // chooser.
   RequestDeviceSession* const session = new RequestDeviceSession(
       thread_id, request_id, frame_routing_id, requesting_origin, filters,
       optional_services_blacklist_filtered);
   int chooser_id = request_device_sessions_.Add(session);
 
   BluetoothChooser::EventHandler chooser_event_handler =
@@ skipping 424 matching lines @@
 
 bool BluetoothDispatcherHost::CanFrameAccessCharacteristicInstance(
     int frame_routing_id,
     const std::string& characteristic_instance_id) {
   return QueryCacheForCharacteristic(GetOrigin(frame_routing_id),
                                      characteristic_instance_id)
              .outcome != CacheQueryOutcome::BAD_RENDERER;
 }
 
 }  // namespace content