Use ICU plural syntax in more place

extensions/browser/api/device_permissions_prompt.cc

Index: extensions/browser/api/device_permissions_prompt.cc
diff --git a/extensions/browser/api/device_permissions_prompt.cc b/extensions/browser/api/device_permissions_prompt.cc
index 6e630456747cdadf7f98677b59d5f2cf24b95c06..a0b5df88a0853ea9d3d93f4ca2ab8fa968799cf1 100644
--- a/extensions/browser/api/device_permissions_prompt.cc
+++ b/extensions/browser/api/device_permissions_prompt.cc
@@ -104,9 +104,8 @@ class UsbDevicePermissionsPrompt : public DevicePermissionsPrompt::Prompt,
   }
 
   base::string16 GetHeading() const override {
-    return l10n_util::GetStringUTF16(
-        multiple() ? IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE_MULTIPLE
-                   : IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE_SINGLE);
+    return l10n_util::GetPluralStringFUTF16(
+        IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE, devices_.size());
   }
 
   void Dismissed() override {
@@ -197,6 +196,7 @@ void DevicePermissionsPrompt::Prompt::SetObserver(Observer* observer) {
 }
 
 base::string16 DevicePermissionsPrompt::Prompt::GetPromptMessage() const {
+  // TODO(jungshik): Consider using the ICU syntax once bug 481734 is fixed.
   return l10n_util::GetStringFUTF16(multiple_
                                         ? IDS_DEVICE_PERMISSIONS_PROMPT_MULTIPLE
                                         : IDS_DEVICE_PERMISSIONS_PROMPT_SINGLE,