Put the RenderFrame's ID into a per-frame WebBluetooth, and plumb that back to the browser.

content/renderer/render_frame_impl.cc

 // Copyright 2013 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.
 
 #include "content/renderer/render_frame_impl.h"
 
 #include <map>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 3788 matching lines @@
                                                 const WebURL& url) {
   bool user_gesture = WebUserGestureIndicator::isProcessingUserGesture();
   Send(new FrameHostMsg_UnregisterProtocolHandler(routing_id_,
                                                   base::UTF16ToUTF8(scheme),
                                                   url,
                                                   user_gesture));
 }
 
 blink::WebBluetooth* RenderFrameImpl::bluetooth() {
   if (!bluetooth_) {
-    bluetooth_.reset(
-        new WebBluetoothImpl(ChildThreadImpl::current()->thread_safe_sender()));
+    bluetooth_.reset(new WebBluetoothImpl(
+        ChildThreadImpl::current()->thread_safe_sender(), routing_id_));
   }
 
   return bluetooth_.get();
 }
 
 #if defined(ENABLE_WEBVR)
 blink::WebVRClient* RenderFrameImpl::webVRClient() {
   if (!vr_dispatcher_)
     vr_dispatcher_.reset(new VRDispatcher(GetServiceRegistry()));
 
@@ skipping 1223 matching lines @@
 void RenderFrameImpl::RegisterMojoServices() {
   // Only main frame have ImageDownloader service.
   if (!frame_->parent()) {
     GetServiceRegistry()->AddService<image_downloader::ImageDownloader>(
         base::Bind(&ImageDownloaderImpl::CreateMojoService,
                    base::Unretained(this)));
   }
 }
 
 }  // namespace content