Add/improve ChromeVox feedback for switches

chrome/browser/resources/chromeos/chromevox/strings/chromevox_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <grit base_dir="." current_release="1" latest_public_release="0"
       output_all_resource_defines="false" enc_check="möl" source_lang_id="en">
   <outputs>
     <output filename="_locales/am/messages.json" type="chrome_messages_json" lang="am"/>
     <output filename="_locales/ar/messages.json" type="chrome_messages_json" lang="ar"/>
     <output filename="_locales/bg/messages.json" type="chrome_messages_json" lang="bg"/>
     <output filename="_locales/bn/messages.json" type="chrome_messages_json" lang="bn"/>
     <output filename="_locales/ca/messages.json" type="chrome_messages_json" lang="ca"/>
@@ skipping 546 matching lines @@
       </message>
       <message desc="The checked state for a checkbox." name="IDS_CHROMEVOX_CHECKBOX_CHECKED_STATE">
         checked
       </message>
       <message desc="Describes a HTML checkbox named 'name' in the unchecked state." name="IDS_CHROMEVOX_DESCRIBE_CHECKBOX_UNCHECKED">
         <ph name="name">$1</ph>, checkbox not checked
       </message>
       <message desc="The unchecked state for a checkbox." name="IDS_CHROMEVOX_CHECKBOX_UNCHECKED_STATE">
         not checked
       </message>
+      <message desc="Describes a switch named 'name' in the on/checked state." name="IDS_CHROMEVOX_DESCRIBE_SWITCH_ON">
+        <ph name="name">$1</ph>, switch on
+      </message>
+      <message desc="Describes a switch named 'name' in the off/unchecked state." name="IDS_CHROMEVOX_DESCRIBE_SWITCH_OFF">
+        <ph name="name">$1</ph>, switch off
+      </message>
       <message desc="Describes a HTML radio button named 'name' in the selected state." name="IDS_CHROMEVOX_DESCRIBE_RADIO_SELECTED">
         <ph name="name">$1</ph>, radio button selected
       </message>
       <message desc="The selected state for a radio button." name="IDS_CHROMEVOX_RADIO_SELECTED_STATE">
         selected
       </message>
       <message desc="Describes a HTML radio button named 'name' in the unselected state." name="IDS_CHROMEVOX_DESCRIBE_RADIO_UNSELECTED">
         <ph name="name">$1</ph>, radio button unselected
       </message>
       <message desc="The unselected state for a radio button." name="IDS_CHROMEVOX_RADIO_UNSELECTED_STATE">
@@ skipping 2004 matching lines @@
       </message>
       <message desc="Describes a UI element invoked after pressing enter such as an ok button in a dialog" name="IDS_CHROMEVOX_DEFAULT_STATE">
         default
       </message>
       <message desc="Brailles for a UI element invoked after pressing enter such as an ok button in a dialog" name="IDS_CHROMEVOX_DEFAULT_STATE_BRL">
         default
       </message>
     </messages>
   </release>
 </grit>