Add a kill switch for all of Web Bluetooth.

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index 34ff478dd0e8fcbd585372014f3dca41ffd99086..7786c2a24c33a8eeb82f413c7767a5e35b4a100a 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -418,9 +418,15 @@ class CONTENT_EXPORT ContentBrowserClient {
 
   // Allow the embedder to control whether we can use Web Bluetooth.
   // TODO(crbug.com/589228): Replace this with a use of the permission system.
-  virtual bool AllowWebBluetooth(content::BrowserContext* browser_context,
-                                 const url::Origin& requesting_origin,
-                                 const url::Origin& embedding_origin);
+  enum class AllowWebBluetoothResult {
+    ALLOW,
+    BLOCK_POLICY,
+    BLOCK_KILL_SWITCH,

[jam, 2016/03/29 18:06:18]

can we keep the "kill switch" concept out of content, since it's a chrome level
thing? the webkit mapping says "Web Bluetooth permission globally disabled", so
perhaps this can be BLOCK_GLOBALLY_DISABLED?

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

Sure, unless Kendra wants to argue that it ought to be a content/web-level
thing. I've made this change assuming she won't.

[kcarattini, 2016/03/30 00:45:59]

No argument here.

+  };
+  virtual AllowWebBluetoothResult AllowWebBluetooth(
+      content::BrowserContext* browser_context,
+      const url::Origin& requesting_origin,
+      const url::Origin& embedding_origin);
 
   // Allow the embedder to override the request context based on the URL for
   // certain operations, like cookie access. Returns nullptr to indicate the