Revise user-data-dir switch handling; avoid crashes.

chrome/app/chromium_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This file contains definitions of strings that are distribution specific.
 These strings will not be translated and only english versions will
 be available for now. -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       source_lang_id="en" enc_check="möl">
   <outputs>
     <output filename="grit/chromium_strings.h" type="rc_header">
       <emit emit_type='prepend'></emit>
@@ skipping 480 matching lines @@
       <if expr="is_macosx">
         <message name="IDS_PASSWORDS_PAGE_AUTHENTICATION_PROMPT" desc="Text for the dialog box that prompts the user for their OS account password before revealing plaintext passwords on the password page.">
           Chromium is trying to show passwords.
         </message>
       </if>
       <if expr="is_win">
         <message name="IDS_PASSWORDS_PAGE_AUTHENTICATION_PROMPT" desc="Text for the dialog box that prompts the user for their OS account password before revealing plaintext passwords on the password page.">
           Chromium is trying to show passwords. Type your Windows password to allow this.
         </message>
       </if>
-      <message name="IDS_CANT_WRITE_USER_DIRECTORY_EXIT_BUTTON" desc="Text on button of dialog that closes Chrome if we can't create a directory for this user.">
-        Exit Chromium
-      </message>
       <message name="IDS_MACHINE_LEVEL_INSTALL_CONFLICT" desc="Error message to display when user tries to run user level Chromium even though machine level Chromium is already installed.">
         An administrator has installed Chromium on this system, and it is available for all users. The system-level Chromium will replace your user-level installation now.
       </message>
       <message name="IDS_INSTALL_HIGHER_VERSION" desc="Error displayed when higher version already exists.">
         This computer already has a more recent version of Chromium. If the software is not working, please uninstall Chromium and try again.
       </message>
       <message name="IDS_INSTALL_HIGHER_VERSION_APP_LAUNCHER" desc="Error displayed when higher version of the Chromium App Launcher already exists.">
         This computer already has a more recent version of the Chromium components. Please use a more recent installer.
       </message>
       <message name="IDS_INSTALL_FAILED" desc="Error displayed if installation fails due to some unknown error.">
@@ skipping 537 matching lines @@
       </message>
 
       <!-- ProcessSingleton -->
       <message name="IDS_PROFILE_IN_USE_LINUX" desc="Message shown when the browser cannot start because the profile is in use on a different host.">
         The profile appears to be in use by another Chromium process (<ph name="PROCESS_ID">$1<ex>12345</ex></ph>) on another computer (<ph name="HOST_NAME">$2<ex>example.com</ex></ph>). Chromium has locked the profile so that it doesn't get corrupted. If you are sure no other processes are using this profile, you can unlock the profile and relaunch Chromium.
       </message>
 
     </messages>
   </release>
 </grit>