[Android] Edit page info permissions string description

Update the description in order to provide context for translators on
how to handle the case with languages with adjective gender agreements.

Bug: 1077766
Change-Id: Ib6721105f2192e46167ece437d69822326501b15
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2428890
Commit-Queue: Ehimare Okoyomon <eokoyomon@chromium.org>
Reviewed-by: Christian Dullweber <dullweber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810556}

components/browser_ui/strings/android/browser_ui_strings.grd

@@ -450,7 +450,9 @@
       <message name="IDS_PAGE_INFO_PERMISSIONS_SUMMARY_1_BLOCKED" desc="Summary page info permissions string for for one blocked permission.">
         <ph name="PERMISSION_1">%1$s<ex>Location</ex></ph> blocked
       </message>
-      <message name="IDS_PAGE_INFO_PERMISSIONS_SUMMARY_2_MIXED" desc="Summary page info permissions string for 2 permissions, with a mix of allowed/blocked.">
+      <message name="IDS_PAGE_INFO_PERMISSIONS_SUMMARY_2_MIXED" desc="Summary page info permissions string for 2 permissions, with a mix of allowed/blocked.
+      For the languages in which allowed/blocked have to agree with the gender of the permission, a translation of the string 'PERMISSION_1 and PERMISSION_2' should be used instead.
+      Refer to b/168814348 for more details.">
         <ph name="PERMISSION_1">%1$s<ex>Location</ex></ph> allowed, <ph name="PERMISSION_2">%2$s<ex>Sound</ex></ph> blocked
       </message>
       <message name="IDS_PAGE_INFO_PERMISSIONS_SUMMARY_2_ALLOWED" desc="Summary page info permissions string for 2 permissions, all allowed.">