Add message and Help Center link to the chooser UI

chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc

Index: chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc
diff --git a/chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc b/chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc
index 7db53f219718fc244b83ae32966e3166541fc39e..d1092435d8980b1016dca218b6a27e7d401f30e8 100644
--- a/chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc
+++ b/chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.cc
@@ -5,7 +5,9 @@
 #include "chrome/browser/ui/bluetooth/bluetooth_chooser_bubble_delegate.h"
 
 #include "base/stl_util.h"
+#include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/ui/bluetooth/bluetooth_chooser_desktop.h"
+#include "chrome/common/url_constants.h"
 #include "components/bubble/bubble_controller.h"
 
 BluetoothChooserBubbleDelegate::BluetoothChooserBubbleDelegate(
@@ -56,6 +58,10 @@ void BluetoothChooserBubbleDelegate::Close() {
   }
 }
 
+base::string16 BluetoothChooserBubbleDelegate::GetHelpCenterUrl() const {
+  return base::ASCIIToUTF16(chrome::kChooserBluetoothOverviewURL);

[msw, 2016/02/22 20:13:11]

Avoid converting to string16 before creating the GURL.

[juncai, 2016/02/22 22:06:37]

Explained in another comment for why using base::string16.

+}
+
 void BluetoothChooserBubbleDelegate::AddDevice(
     const std::string& device_id,
     const base::string16& device_name) {