Add a kill switch for all of Web Bluetooth.

content/browser/bluetooth/bluetooth_dispatcher_host.cc

Index: content/browser/bluetooth/bluetooth_dispatcher_host.cc
diff --git a/content/browser/bluetooth/bluetooth_dispatcher_host.cc b/content/browser/bluetooth/bluetooth_dispatcher_host.cc
index b69fa4fa49f19a3632cda132998f947eec1a764d..677ed1dcaac855bbbde22182d29fe9fc08840b5a 100644
--- a/content/browser/bluetooth/bluetooth_dispatcher_host.cc
+++ b/content/browser/bluetooth/bluetooth_dispatcher_host.cc
@@ -1219,14 +1219,32 @@ void BluetoothDispatcherHost::OnRequestDeviceImpl(
     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(
+      web_contents->GetBrowserContext(), requesting_origin, embedding_origin)) {
+    case ContentBrowserClient::AllowWebBluetoothResult::BLOCK_POLICY: {
+      RecordRequestDeviceOutcome(
+          UMARequestDeviceOutcome::BLUETOOTH_CHOOSER_POLICY_DISABLED);
+      Send(new BluetoothMsg_RequestDeviceError(
+          thread_id, request_id,
+          WebBluetoothError::ChooserNotShown_APILocallyDisabled));
+      return;
+    }
+    case ContentBrowserClient::AllowWebBluetoothResult::
+        BLOCK_GLOBALLY_DISABLED: {
+      // Log to the developer console.
+      web_contents->GetMainFrame()->AddMessageToConsole(
+          content::CONSOLE_MESSAGE_LEVEL_LOG,
+          "Bluetooth permission has been blocked.");
+      // Block requests.
+      RecordRequestDeviceOutcome(
+          UMARequestDeviceOutcome::BLUETOOTH_GLOBALLY_DISABLED);
+      Send(new BluetoothMsg_RequestDeviceError(
+          thread_id, request_id,
+          WebBluetoothError::ChooserNotShown_APIGloballyDisabled));
+      return;
+    }
+    case ContentBrowserClient::AllowWebBluetoothResult::ALLOW:
+      break;
   }
 
   // Create storage for the information that backs the chooser, and show the
@@ -1379,7 +1397,7 @@ void BluetoothDispatcherHost::FinishClosingChooser(
     VLOG(1) << "Bluetooth chooser denied permission";
     Send(new BluetoothMsg_RequestDeviceError(
         session->thread_id, session->request_id,
-        WebBluetoothError::ChooserDeniedPermission));
+        WebBluetoothError::ChooserNotShown_BrowserDeniedPermissionToScan));

[ortuno, 2016/03/30 19:19:46]

I think you might have meant to change the error in line 1274. In this case we
do show the chooser; that's where the user can press the "Update Permission"
option and that will request for the permission.

[Jeffrey Yasskin, 2016/03/30 19:31:24]

Line 1274 is just the chooser event saying that it can't ask for permission to
scan. That event comes down here and closes the chooser with a message to the
website that it can't ask for permission anymore.

It's true that we might have shown the chooser before being denied permission to
ask again, but on future calls we won't show it, since we can't ask, and the
website instead needs to guide users to re-enable the permission.

When we simply don't have permission but can ask, we shouldn't return this
error. Let me know if you see a path where we would.

[ortuno, 2016/03/30 19:41:51]

Ah you're totally right.

     request_device_sessions_.Remove(chooser_id);
     return;
   }