Remove unused string and fix punctuation in IDS_PAGE_INFO_INTERNAL_PAGE

BUG=688621

Review-Url: https://codereview.chromium.org/2684973013
Cr-Commit-Position: refs/heads/master@{#450041}
diff --git a/components/components_chromium_strings.grd b/components/components_chromium_strings.grd
index 7eee274..87be555 100644
--- a/components/components_chromium_strings.grd
+++ b/components/components_chromium_strings.grd
@@ -210,7 +210,7 @@
 
       <!-- Page Info bubble -->
       <message name="IDS_PAGE_INFO_INTERNAL_PAGE" desc="Message to display in the page info bubble when the page you are on is a chrome:// page or about:something.">
-        You are viewing a secure Chromium page.
+        You're viewing a secure Chromium page
       </message>
 
       <message name="IDS_SESSION_CRASHED_VIEW_MESSAGE" desc="Message shown when the last session didn't exit cleanly.">