[Onion Soup] Move WebBluetoothImpl from //content/renderer/bluetooth to Blink's bluetooth module

content/browser/frame_host/render_frame_host_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/browser/frame_host/render_frame_host_impl.h"
 
+#include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/debug/dump_without_crashing.h"
 #include "base/lazy_instance.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/process/kill.h"
@@ skipping 3205 matching lines @@
   if (!focused_frame_tree_node)
     return;
   RenderFrameHostImpl* focused_frame =
       focused_frame_tree_node->current_frame_host();
   DCHECK(focused_frame);
   dst->focused_tree_id = focused_frame->GetAXTreeID();
 }
 
 WebBluetoothServiceImpl* RenderFrameHostImpl::CreateWebBluetoothService(
     blink::mojom::WebBluetoothServiceRequest request) {
-  DCHECK(!web_bluetooth_service_);
-  web_bluetooth_service_.reset(
-      new WebBluetoothServiceImpl(this, std::move(request)));
-  // RFHI owns web_bluetooth_service_ and web_bluetooth_service owns the
-  // binding_ which may run the error handler. binding_ can't run the error
+  // RFHI owns |web_bluetooth_services_| and |web_bluetooth_service| owns the
+  // |binding_| which may run the error handler. |binding_| can't run the error
   // handler after it's destroyed so it can't run after the RFHI is destroyed.
-  web_bluetooth_service_->SetClientConnectionErrorHandler(base::Bind(
-      &RenderFrameHostImpl::DeleteWebBluetoothService, base::Unretained(this)));
-  return web_bluetooth_service_.get();
+  std::unique_ptr<WebBluetoothServiceImpl> web_bluetooth_service =

[dcheng, 2016/12/27 20:37:37]

Nit: OK to use auto here.

[juncai, 2016/12/27 21:55:50]

Done.

+      base::MakeUnique<WebBluetoothServiceImpl>(this, std::move(request));
+  web_bluetooth_service->SetClientConnectionErrorHandler(
+      base::Bind(&RenderFrameHostImpl::DeleteWebBluetoothService,
+                 base::Unretained(this), web_bluetooth_service.get()));
+  web_bluetooth_services_.push_back(std::move(web_bluetooth_service));

[dcheng, 2016/12/27 20:37:37]

That being said, I've read the code a bit more: I'm wondering why this isn't
just using strong binding? Why does the RFH need to maintain a list of these?

Is it because there are concerns about the lifetimes of the bluetooth service vs
the RFH?

[Reilly Grant (use Gerrit), 2016/12/27 20:45:47]

Yes, this is a common pattern for Mojo service implementations that hold a
RenderFrameHost* (or RenderProcessHost*).

+  return web_bluetooth_services_.back().get();
 }
 
-void RenderFrameHostImpl::DeleteWebBluetoothService() {
-  web_bluetooth_service_.reset();
+void RenderFrameHostImpl::DeleteWebBluetoothService(
+    WebBluetoothServiceImpl* web_bluetooth_service) {
+  auto it = std::find_if(
+      web_bluetooth_services_.begin(), web_bluetooth_services_.end(),
+      [web_bluetooth_service](
+          const std::unique_ptr<WebBluetoothServiceImpl>& service) {
+        return web_bluetooth_service == service.get();
+      });
+  DCHECK(it != web_bluetooth_services_.end());
+  web_bluetooth_services_.erase(it);
 }
 
 void RenderFrameHostImpl::Create(
     const service_manager::Identity& remote_identity,
     media::mojom::InterfaceFactoryRequest request) {
   DCHECK(!media_interface_proxy_);
   media_interface_proxy_.reset(new MediaInterfaceProxy(
       this, std::move(request),
       base::Bind(&RenderFrameHostImpl::OnMediaInterfaceFactoryConnectionError,
                  base::Unretained(this))));
@@ skipping 82 matching lines @@
   // There is no pending NavigationEntry in these cases, so pass 0 as the
   // pending_nav_entry_id. If the previous handle was a prematurely aborted
   // navigation loaded via LoadDataWithBaseURL, propagate the entry id.
   return NavigationHandleImpl::Create(
       params.url, frame_tree_node_, is_renderer_initiated,
       params.was_within_same_page, base::TimeTicks::Now(),
       entry_id_for_data_nav, false);  // started_from_context_menu
 }
 
 }  // namespace content