Implement getMediaDevices.

content/renderer/pepper/pepper_device_enumeration_host_helper.cc

 // Copyright (c) 2012 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/pepper/pepper_device_enumeration_host_helper.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 35 matching lines @@
     // EnumerateDevicesCallbackBody() to ensure that we always call |callback|
     // asynchronously.
     sync_call_ = true;
     request_id_ = owner_->delegate_->EnumerateDevices(
         owner_->device_type_,
         owner_->document_url_,
         base::Bind(&ScopedRequest::EnumerateDevicesCallbackBody, AsWeakPtr()));
     sync_call_ = false;
   }
 
-  ~ScopedRequest() {
-    if (requested_) {
-      owner_->delegate_->StopEnumerateDevices(request_id_);
-    }
-  }
+  ~ScopedRequest() {}

[dmichael (off chromium), 2014/05/27 20:43:23]

Another thing this was doing was canceling the request if
PepperDeviceEnumerationHostHelper goes away before the request has completed.
That could happen I think if the plugin decides to cancel it for some reason, or
the plugin element gets deleted from the DOM.

Might we still want to cancel if the call has not yet completed? I don't know
enough about how expensive EnumerateDevices is to say.

[Henrik Grunell, 2014/05/28 11:08:27]

OK. It sounds like the cancel should be kept. Are you OK with removing the
notification service via the request?

[dmichael (off chromium), 2014/05/28 15:08:37]

I'm not sure what you mean? Do you mean putting the code back how it was, to
call StopEnumerateDevices in the ScopedRequest destructor? I'm fine with that.

 
   bool requested() const { return requested_; }
 
  private:
   void EnumerateDevicesCallbackBody(
       int request_id,
       const std::vector<ppapi::DeviceRefData>& devices) {
     if (sync_call_) {
       base::MessageLoop::current()->PostTask(
           FROM_HERE,
@@ skipping 111 matching lines @@
     uint32_t callback_id,
     int /* request_id */,
     const std::vector<ppapi::DeviceRefData>& devices) {
   resource_host_->host()->SendUnsolicitedReply(
       resource_host_->pp_resource(),
       PpapiPluginMsg_DeviceEnumeration_NotifyDeviceChange(callback_id,
                                                           devices));
 }
 
 }  // namespace content