Add webusb notification UI code

components/webusb/webusb_detector.cc

Index: components/webusb/webusb_detector.cc
diff --git a/components/webusb/webusb_detector.cc b/components/webusb/webusb_detector.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5a3c08ff6f1043e6f6468a75d1e5b60f2a2c7485
--- /dev/null
+++ b/components/webusb/webusb_detector.cc
@@ -0,0 +1,56 @@
+// 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 "components/webusb/webusb_detector.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "components/webusb/webusb_browser_client.h"
+#include "device/core/device_client.h"
+#include "device/usb/usb_device.h"
+#include "device/usb/usb_ids.h"
+
+namespace webusb {
+
+WebUsbDetector::WebUsbDetector(Profile* profile)
+    : profile_(profile), observer_(this) {
+  Initialize();
+}
+
+WebUsbDetector::~WebUsbDetector() {}
+
+void WebUsbDetector::Shutdown() {}
+
+void WebUsbDetector::Initialize() {
+  if (!webusb::WebUsbBrowserClient::Get()->WebUsbNotificationEnabled()) {
+    return;
+  }
+
+  device::UsbService* usb_service =
+      device::DeviceClient::Get()->GetUsbService();
+  if (!usb_service)
+    return;
+  observer_.Add(usb_service);
+}
+
+void WebUsbDetector::OnDeviceAdded(scoped_refptr<device::UsbDevice> device) {
+  const char* product_name =
+      device::UsbIds::GetProductName(device->vendor_id(), device->product_id());
+  if (!product_name) {
+    return;
+  }
+
+  const GURL& landing_page = device->webusb_landing_page();
+  if (!landing_page.is_valid()) {
+    return;
+  }
+
+  webusb::WebUsbBrowserClient::Get()->OnDeviceAdded(
+      profile_, product_name, landing_page, device->guid());
+}
+
+void WebUsbDetector::OnDeviceRemoved(scoped_refptr<device::UsbDevice> device) {
+  webusb::WebUsbBrowserClient::Get()->OnDeviceRemoved(device->guid());
+}
+
+}  // namespace webusb