Update title for offline interstitials

Makes the string consistent with other Google products.

Bug: 836214
Change-Id: I28a3fa35be8c29960b93eed208acd934a4eb4787
Reviewed-on: https://chromium-review.googlesource.com/1025098Reviewed-by: Edward Jung <edwardjung@chromium.org>
Reviewed-by: Matt Menke <mmenke@chromium.org>
Commit-Queue: Edward Jung <edwardjung@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553163}

components/error_page_strings.grdp

@@ -104,16 +104,9 @@
   <message name="IDS_ERRORPAGES_HEADING_NETWORK_ACCESS_DENIED" desc="Heading of the error page when we're not being allowed to access the network.">
     Your Internet access is blocked
   </message>
-  <if expr="not is_android">
-    <message name="IDS_ERRORPAGES_HEADING_INTERNET_DISCONNECTED" desc="Heading of the error page when the network connection failed.">
-      There is no Internet connection
-    </message>
-  </if>
-  <if expr="is_android">
-    <message name="IDS_ERRORPAGES_HEADING_INTERNET_DISCONNECTED" desc="Mobile: Heading of the error page when the network connection failed.">
-      You are offline.
-    </message>
-  </if>
+  <message name="IDS_ERRORPAGES_HEADING_INTERNET_DISCONNECTED" desc="Heading of the error page when the network connection failed.">
+    No internet
+  </message>
   <message name="IDS_ERRORPAGES_HEADING_CACHE_READ_FAILURE" desc="Heading in the error page when we encountered an error reading from the cache.  Generally this happens when the disk cache is corrupted from improper shutdown.">
     This site can’t be loaded from the cache
   </message>