[CUPS] Implement the UI handler for adding a new printer.

chrome/app/settings_strings.grdp

Index: chrome/app/settings_strings.grdp
diff --git a/chrome/app/settings_strings.grdp b/chrome/app/settings_strings.grdp
index cf3a9ef42027c27851a01aef79c712fc828ce2a1..225bdf8a991c6707367eb01c12d899f857a89f89 100644
--- a/chrome/app/settings_strings.grdp
+++ b/chrome/app/settings_strings.grdp
@@ -837,6 +837,9 @@
     <message name="IDS_SETTINGS_PRINTING_CUPS_PRINTER_BUTTON_SELECT_DRIVER" desc="Text for the button which allows user to select a PPD file from the file system.">
       Browse
     </message>
+    <message name="IDS_SETTINGS_PRINTING_CUPS_PRINTER_ADDED_PRINTER_MESSAGE" desc="The message shown when a new printer is set up successfully.">
+      Added <ph name="PRINTER_NAME">$1<ex>printer</ex></ph>
+    </message>
   </if>
   <message name="IDS_SETTINGS_PRINTING_CLOUD_PRINTERS" desc="In Printing Settings, the title of the google cloud printers setting section.">
     Google Cloud Print