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
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index 0000000000000000000000000000000000000000..0cb2c4625fb2d5105eaa464e2182bf299c858759
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+// 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 "base/memory/singleton.h"
+#include "base/strings/string16.h"
+#include "base/strings/utf_string_conversions.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"
+#include "grit/components_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/gfx/image/image.h"
+#include "ui/message_center/message_center.h"
+#include "ui/message_center/notification.h"
+#include "ui/message_center/notification_delegate.h"
+
+namespace {
+
+const char kWebUsbDetectorNotificationID[] = "webusb.detector";
+
+// Delegate for webusb notification
+class WebUsbNotificationDelegate : public message_center::NotificationDelegate {
+ public:
+  WebUsbNotificationDelegate(const GURL& landing_page,
+                             const std::string& notification_id)
+      : landing_page_(landing_page), notification_id_(notification_id) {}
+
+  void Click() override {
+    webusb::WebUsbBrowserClient::Get()->OpenURL(landing_page_);
+    message_center::MessageCenter::Get()->RemoveNotification(
+        notification_id_, false /* by_user */);
+  }
+
+ private:
+  ~WebUsbNotificationDelegate() override = default;
+
+  GURL landing_page_;
+  std::string notification_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebUsbNotificationDelegate);
+};
+
+}  // namespace
+
+namespace webusb {
+
+WebUsbDetector* WebUsbDetector::GetInstance() {
+  return Singleton<WebUsbDetector>::get();
+}
+
+WebUsbDetector::WebUsbDetector() : observer_(this) {
+  Initialize();
+}
+
+WebUsbDetector::~WebUsbDetector() {}
+
+void WebUsbDetector::Initialize() {
+  if (!webusb::WebUsbBrowserClient::Get()) {
+    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());

[Reilly Grant (use Gerrit), 2015/08/20 17:02:45]

Prefer the product name from device->product_string() over the value provided by
UsbIds. I'm actually tempted to say we don't want to query UsbIds ever for
WebUSB devices.

[juncai, 2015/08/21 05:16:04]

Done.

+  if (!product_name) {
+    return;
+  }
+
+  const GURL& landing_page = device->webusb_landing_page();
+  if (!landing_page.is_valid()) {
+    return;
+  }
+
+  std::string notification_id = device->guid();
+
+  scoped_ptr<message_center::Notification> notification;
+
+  message_center::RichNotificationData rich_notification_data;
+  rich_notification_data.context_message =
+      base::UTF8ToUTF16(landing_page.GetContent());
+
+  notification.reset(new message_center::Notification(
+      message_center::NOTIFICATION_TYPE_SIMPLE, notification_id,
+      l10n_util::GetStringFUTF16(IDS_WEBUSB_DEVICE_DETECTED_NOTIFICATION_TITLE,
+                                 base::UTF8ToUTF16(product_name)),
+      l10n_util::GetStringUTF16(IDS_WEBUSB_DEVICE_DETECTED_NOTIFICATION),
+      // TODO(juncai): use generic USB device icon here.
+      gfx::Image(), base::string16(),
+      message_center::NotifierId(message_center::NotifierId::SYSTEM_COMPONENT,
+                                 kWebUsbDetectorNotificationID),
+      rich_notification_data,
+      new WebUsbNotificationDelegate(landing_page, notification_id)));
+
+  notification->SetSystemPriority();
+  message_center::MessageCenter::Get()->AddNotification(notification.Pass());
+}
+
+void WebUsbDetector::OnDeviceRemoved(scoped_refptr<device::UsbDevice> device) {
+  std::string notification_id = device->guid();
+
+  message_center::MessageCenter* message_center =
+      message_center::MessageCenter::Get();
+  if (message_center->FindVisibleNotificationById(notification_id)) {
+    message_center->RemoveNotification(notification_id, false /* by_user */);
+  }
+}
+
+}  // namespace webusb