Match WebUSB errors more closely to the specificiation.

content/renderer/usb/web_usb_client_impl.cc

 // Copyright 2015 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/usb/web_usb_client_impl.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/move.h"
@@ skipping 28 matching lines @@
 }
 
 // Create a new ScopedWebCallbacks for WebUSB client callbacks, defaulting to
 // a "no service" rejection.
 template <typename CallbacksType>
 ScopedWebCallbacks<CallbacksType> MakeScopedUSBCallbacks(
     CallbacksType* callbacks) {
   return make_scoped_web_callbacks(
       callbacks,
       base::Bind(&RejectCallbacksWithError<CallbacksType>,
-                 blink::WebUSBError(blink::WebUSBError::Error::Service,
-                                    base::UTF8ToUTF16(kNoServiceError))));
+                 blink::WebUSBError(blink::WebUSBError::Error::NotFound,
+                                    base::ASCIIToUTF16(kNoServiceError))));
 }
 
 void OnGetDevicesComplete(
     ScopedWebCallbacks<blink::WebUSBClientGetDevicesCallbacks> scoped_callbacks,
     device::usb::DeviceManager* device_manager,
     mojo::Array<device::usb::DeviceInfoPtr> results) {
   blink::WebVector<blink::WebUSBDevice*>* devices =
       new blink::WebVector<blink::WebUSBDevice*>(results.size());
   for (size_t i = 0; i < results.size(); ++i) {
     device::usb::DevicePtr device;
@@ skipping 10 matching lines @@
     device::usb::DeviceInfoPtr result) {
   auto scoped_callbacks = callbacks.PassCallbacks();
   if (result) {
     device::usb::DevicePtr device;
     device_manager->GetDevice(result->guid, mojo::GetProxy(&device));
     blink::WebUSBDevice* web_usb_device = new WebUSBDeviceImpl(
         device.Pass(), mojo::ConvertTo<blink::WebUSBDeviceInfo>(result));
 
     scoped_callbacks->onSuccess(blink::adoptWebPtr(web_usb_device));
   } else {
-    scoped_callbacks->onSuccess(
-        blink::adoptWebPtr<blink::WebUSBDevice>(nullptr));
+    scoped_callbacks->onError(
+        blink::WebUSBError(blink::WebUSBError::Error::NotFound,
+                           base::ASCIIToUTF16("No device selected.")));
   }
 }
 
 }  // namespace
 
 WebUSBClientImpl::WebUSBClientImpl(content::ServiceRegistry* service_registry)
     : service_registry_(service_registry) {}
 
 WebUSBClientImpl::~WebUSBClientImpl() {}
 
@@ skipping 63 matching lines @@
     const device::usb::DeviceInfoPtr& device_info =
         notification->devices_removed[i];
     device::usb::DevicePtr device;
     device_manager_->GetDevice(device_info->guid, mojo::GetProxy(&device));
     observer_->onDeviceDisconnected(blink::adoptWebPtr(new WebUSBDeviceImpl(
         device.Pass(), mojo::ConvertTo<blink::WebUSBDeviceInfo>(device_info))));
   }
 }
 
 }  // namespace content