[omnibox] Add accessibility strings for Remove Button

This adds accessibility strings, just like the Tab Switch button has.

It adds two PREFIX variants  for when the button is focused.

It doesn't add the SUFFIX variant, because so many suggestions have
the removal feature, we don't want to be constantly announcing it.

There are no screenshots because this is just a accessibility TTS
announcement, with no graphical representation.

Bug: 1036453, 1205
Change-Id: I0c2eac9fb2ba52e9ce01afa6e3e1d45f75bc0491
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1979286Reviewed-by: manuk hovanesian <manukh@chromium.org>
Commit-Queue: Tommy Li <tommycli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#726933}

components/omnibox_strings.grdp

@@ -231,6 +231,13 @@
   <message name="IDS_ACC_TAB_SWITCH_BUTTON" desc="Announcement when tab switch button focused.">
     Tab switch button, press Enter to switch to this tab
   </message>
+  <!-- Accessibility suffix for suggestions when the remove button is focused.-->
+  <message name="IDS_ACC_REMOVE_SUGGESTION_FOCUSED_PREFIX" desc="Announcement when remove suggestion button is focused.">
+    Remove Suggestion button, press Enter to remove, <ph name="REMOVE_BUTTON_FOCUSED_FRIENDLY_MATCH_TEXT">$1<ex>The Chromium Projects http://www.chromium.org bookmark</ex></ph>
+  </message>
+  <message name="IDS_ACC_REMOVE_SUGGESTION_BUTTON" desc="Announcement when remove suggestion button is focused.">
+    Remove Suggestion button, press Enter to remove this suggestion
+  </message>
   <message name="IDS_ACC_EXIT_SEARCH_MODE" desc="Announcement when Omnibox exits keyword search mode.">
     Exiting search mode
   </message>