This is UI side unreadable device support.

chrome/app/generated_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!--
 This file contains definitions of resources that will be translated for each
 locale.  The variables is_win, is_macosx, is_linux, and is_posix are available
 for making strings OS specific.  Other platform defines such as use_titlecase
 are declared in build/common.gypi.
 -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
@@ skipping 9158 matching lines @@
         Show all files
       </message>
 
      <message name="IDS_FILE_BROWSER_CONFIRM_DELETE_ONE" desc="Asks the user if they are sure they want to delete a single file.">
        Are you sure you want to delete "$1"?
      </message>
      <message name="IDS_FILE_BROWSER_CONFIRM_DELETE_SOME" desc="Asks the user if they are sure they want to delete multiple files/directories.">
        Are you sure you want to delete $1 items?
      </message>
 
+      <message name="IDS_FILE_BROWSER_UNKNOWN_FILESYSTEM_WARNING" desc="Displayed when device contents cannot be read because filesystem is unknown.">
+        This device cannot be opened because its filesystem was not recognized.
+      </message>
+      <message name="IDS_FILE_BROWSER_UNSUPPORTED_FILESYSTEM_WARNING" desc="Displayed when device contents cannot be read because filesystem is unsupported.">
+        This device cannot be opened because its filesystem is not supported.
+      </message>
       <message name="IDS_FILE_BROWSER_FORMATTING_WARNING" desc="Displayed when you attempt to format device.">
         Formatting the removable media is going to erase all data. Do you wish to continue?
       </message>
 
       <message name="IDS_FILE_BROWSER_SELECT_FOLDER_TITLE" desc="Select folder title.">
         Select a folder to open
       </message>
       <message name="IDS_FILE_BROWSER_SELECT_OPEN_FILE_TITLE" desc="Select open file title.">
         Select a file to open
       </message>
@@ skipping 4289 matching lines @@
       </if>
     </includes>
     <structures fallback_to_english="true">
       <structure name="IDD_CHROME_FRAME_FIND_DIALOG" file="cf_resources.rc" type="dialog" >
       </structure>
       <structure name="IDD_CHROME_FRAME_READY_PROMPT" file="cf_resources.rc" type="dialog" >
       </structure>
     </structures>
   </release>
 </grit>