MD Extensions: Add more i18n context to text for "Related to NAME_PH".

String remains the same, but context is expanded on.

Bug: b/71972241
Change-Id: I522cb01d840fcc7204448c9c40dcfa869ee0e543
Reviewed-on: https://chromium-review.googlesource.com/876951Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Hector Carmona <hcarmona@chromium.org>
Cr-Commit-Position: refs/heads/master@{#530689}

chrome/app/md_extensions_strings.grdp

@@ -75,7 +75,7 @@
   <message name="IDS_MD_EXTENSIONS_ITEM_DETAILS" desc="The text on the button to show more details for a given extension.">
     Details
   </message>
-  <message name="IDS_MD_EXTENSIONS_EXTENSION_A11Y_ASSOCIATION" desc="Label used to associate an app or extension with actions for screen readers. This will only be read out lout.">
+  <message name="IDS_MD_EXTENSIONS_EXTENSION_A11Y_ASSOCIATION" desc="Label used to associate an app or extension with actions a user can take. This label is for screen readers and will only be read out lout. Ex: a button labeled 'Delete' would have the description 'Related to AdBlock'. Without the added description a user on a screen reader would not have context of the extension they want to delete. Note that the action can be 'view details', 'enable', 'delete', 'errors', or something else.">
     Related to <ph name="NAME_PH">$1<ex>AdBlock</ex></ph>
   </message>
   <message name="IDS_MD_EXTENSIONS_APP_ICON" desc="The alt text for the app's icon. Used for accessibility.">