Use ICU plural syntax in more place

extensions/extensions_strings.grd

 <?xml version="1.0" encoding="utf-8"?>
 
 <!--
   Strings for the extensions module. Used mostly for low-level error messages.
   Where possible new strings should be kept in Chrome and the extensions module
   should return an error code, message flag, etc.
 -->
 
 <grit latest_public_release="0" current_release="1"
       source_lang_id="en" enc_check="möl">
@@ skipping 323 matching lines @@
         Exchange data with the device named <ph name="HOSTNAME">$1<ex>foo.example.com</ex></ph>
       </message>
       <message name="IDS_EXTENSION_PROMPT_WARNING_SOCKET_SPECIFIC_HOSTS" desc="Permission string for access to multiple specific devices on the local network or internet.">
         Exchange data with the devices named: <ph name="HOSTNAMES">$1<ex>foo.example.com bar.example.com</ex></ph>
       </message>
 
       <!-- Device API strings. Please keep alphabetized. -->
       <message name="IDS_DEVICE_PERMISSIONS_DEVICE_NAME" desc="String describing a device in a list of devices.">
         <ph name="PRODUCT_NAME">$1<ex>SoundKnob</ex></ph> from <ph name="VENDOR_NAME">$2<ex>Griffin Technology</ex></ph>
       </message>
-      <message name="IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE_SINGLE" desc="Title of the USB device selection dialog when the app wants only one device selected.">
-        Select a USB device
-      </message>
-      <message name="IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE_MULTIPLE" desc="Title of the USB device selection dialog when the app will accept one or more selected devices.">
-        Select USB devices
+      <message name="IDS_USB_DEVICE_PERMISSIONS_PROMPT_TITLE" desc="Title of the USB device selection dialog when the app will accept one or more selected devices. If a langugage has a generic plural (larger than one), use that for all sub-messages other than '=1'. [ICU Syntax]">
+      {NUM_DEVICE, plural,
+      =1 {Select a USB device} other {Select USB devices}}
       </message>
       <message name="IDS_DEVICE_PERMISSIONS_PROMPT_SINGLE" desc="Instructions asking the user to select one device for use with an app.">
         The application "<ph name="APP_NAME">$1<ex>Chrome Dev Editor</ex></ph>" is requesting access to one of your devices.
       </message>
       <message name="IDS_DEVICE_PERMISSIONS_PROMPT_MULTIPLE" desc="Instructions asking the user to select one or more devices for use with an app.">
         The application "<ph name="APP_NAME">$1<ex>Chrome Dev Editor</ex></ph>" is requesting access to one or more of your devices.
       </message>
       <message name="IDS_DEVICE_UNKNOWN_PRODUCT" desc="String used when no human-readable product name is available for a device.">
         Product <ph name="PRODUCT_ID">$1<ex>0x1234</ex></ph>
       </message>
@@ skipping 117 matching lines @@
       <!-- Utility process names. Please keep alphabetized. -->
       <message name="IDS_UTILITY_PROCESS_EXTENSION_UNPACKER_NAME" desc="The name of the utility process used for unpacking extensions.">
         Extension Unpacker
       </message>
       <message name="IDS_UTILITY_PROCESS_MANIFEST_PARSER_NAME" desc="The name of the utility process used for parsing extension manifests.">
         Extension Manifest Parser
       </message>
     </messages>
   </release>
 </grit>