Add confirmation dialog when enabling a 3rd party IME.

chrome/browser/resources/options/options.html

Index: chrome/browser/resources/options/options.html
diff --git a/chrome/browser/resources/options/options.html b/chrome/browser/resources/options/options.html
index f99f77361012f5a81bb07c36a49446d9c2f9bab4..f6fcfd48aa3f7153bd5f03d3cf449392aba09267 100644
--- a/chrome/browser/resources/options/options.html
+++ b/chrome/browser/resources/options/options.html
@@ -50,6 +50,7 @@
 <link rel="stylesheet" href="startup_overlay.css">
 <link rel="stylesheet" href="../sync_setup_overlay.css">
 <if expr="chromeos">
+<link rel="stylesheet" href="chromeos/third_party_ime_confirm_overlay.css">
 <link rel="stylesheet" href="chromeos/accounts_options_page.css">
 <link rel="stylesheet" href="chromeos/bluetooth.css">
 <link rel="stylesheet" href="chromeos/change_picture_options.css">
@@ -151,6 +152,7 @@
   <include src="chromeos/display_overscan.html">
   <include src="chromeos/internet_detail.html">
   <include src="chromeos/preferred_networks.html">
+  <include src="chromeos/third_party_ime_confirm_overlay.html">
 </if>
 <if expr="not is_win and not is_macosx">
   <include src="certificate_restore_overlay.html">