Update network error template to new design

chrome/app/chromium_strings.grd

Index: chrome/app/chromium_strings.grd
diff --git a/chrome/app/chromium_strings.grd b/chrome/app/chromium_strings.grd
index b0dd823e47d99723f1e4f1b8eb2ced5fcdc07ded..dbdd893a4dc90e116228da6ad8c3d2dced7acb51 100644
--- a/chrome/app/chromium_strings.grd
+++ b/chrome/app/chromium_strings.grd
@@ -1262,6 +1262,13 @@ Signing in anyway will merge Chromium information like bookmarks, history, and o
       Your computer is running an old version of Microsoft Windows that cannot process this website's security certificate. Because of this problem, Chromium can't tell whether the certificate came from <ph name="SITE">$1<ex>google.com</ex></ph> or from someone on your network pretending to be <ph name="SITE">$1<ex>google.com</ex></ph>. Please update your computer to a more recent version of Windows.
       </message>
 
+      <!-- Offline interstitial  -->
+      <if expr="not is_android and not is_ios">
+        <message name="IDS_ERRORPAGES_SUMMARY_INTERNET_DISCONNECTED" desc="Summary of the error page when the network connection failed. May be followed by platform dependent instructions.">
+        Chromium can’t display the webpage because your computer isn’t connected to the Internet.
+        </message>
+      </if>
+
       <!-- OOBE -->
       <if expr="chromeos">
         <message name="IDS_INSTALLING_UPDATE" desc="Label shown on the updates installation screen during OOBE">