Make password generation switched by a preference in chrome settings rather than a command line fla…

chrome/browser/resources/options2/browser_options.html

 <div id="settings" class="page" hidden>
   <header>
     <h1 i18n-content="settingsTitle"></h1>
   </header>
 <if expr="not pp_ifdef('chromeos')">
   <include src="sync_section.html">
 </if>
 <if expr="pp_ifdef('chromeos')">
   <section>
     <h3 i18n-content="sectionTitleInternet"></h3>
@@ skipping 292 matching lines @@
       <label>
         <input id="password-manager-enabled"
             pref="profile.password_manager_enabled"
             metric="Options_PasswordManager" type="checkbox">
         <span i18n-content="passwordManagerEnabled"></span>
       </label>
       <button id="manage-passwords" class="link-button"
           i18n-content="managePasswords"
           pref="profile.password_manager_enabled"></button>
     </div>
+    <div class="checkbox" id="password-generation-checkbox">
+      <label>
+        <input id="password-generation-enabled" pref="password_generation.enabled"
+            metric="Options_PasswordGenerationCheckbox" type="checkbox">
+        <span i18n-content="passwordGenerationEnabledDescription"></span>
+      </label>
+    </div>
 <if expr="is_macosx">
     <div id="mac-passwords-warning" i18n-content="macPasswordsWarning" hidden>
     </div>
 </if>
     <!-- This makes the managed-banner appear when the "pref" is configured by
          the IT administrator. -->
     <input name="password_allow_show_hidden" type="text"
         pref="profile.password_manager_allow_show_passwords" hidden>
   </section>
   <section id="web-content-section">
@@ skipping 174 matching lines @@
   </section>
 </if>
 </div>  <!-- advanced-settings-container -->
 </div>  <!-- advanced-settings -->
 <footer>
   <button id="advanced-settings-expander" class="link-button"
       i18n-content="showAdvancedSettings">
   </button>
 </footer>
 </div>