[Mfill Android] Improve announcement for keyboard accessory

(This is a modified reland of https://crrev.com/c/1793082)

The keyboard accessory was still using the old announcement. It would
shout "Passwords available" which isn't wrong since passwords fallbacks
are available but it is very imprecise, incomplete and misleading if the
accessory is filled with Address autofill suggestion.

Bug: 1005147
Change-Id: Ie31261aafef6665f8f256abb186cbb4a54fd2852
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1807243
Commit-Queue: Friedrich [CET] <fhorschig@chromium.org>
Reviewed-by: Ioana Pandele <ioanap@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697572}

chrome/android/features/keyboard_accessory/internal/java/res/layout/keyboard_accessory_modern.xml

@@ -8,7 +8,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/keyboard_accessory"
     android:layout_gravity="start|bottom"
-    android:contentDescription="@string/autofill_keyboard_accessory_content_description"
+    android:contentDescription="@string/autofill_keyboard_accessory_modern_content_description"
     android:scrollbars="none"
     android:visibility="gone"
     android:orientation="vertical"

chrome/android/features/keyboard_accessory/internal/java/strings/android_keyboard_accessory_strings.grd

@@ -103,9 +103,12 @@
   </translations>
   <release allow_pseudo="false" seq="1">
     <messages fallback_to_english="true">
-      <message name="IDS_AUTOFILL_KEYBOARD_ACCESSORY_CONTENT_DESCRIPTION" desc="The text announced by the screen reader when the autofill suggestions are shown.">
+      <message name="IDS_AUTOFILL_KEYBOARD_ACCESSORY_CONTENT_DESCRIPTION" desc="The text announced by the screen reader when the password suggestions are shown.">
         Passwords available
       </message>
+      <message name="IDS_AUTOFILL_KEYBOARD_ACCESSORY_MODERN_CONTENT_DESCRIPTION" desc="The text announced by the screen reader when the autofill suggestions and fallbacks are shown.">
+        Autofill suggestions available
+      </message>
       <message name="IDS_KEYBOARD_ACCESSORY_SHEET_HIDE" desc="Description for the active icon button that closes an accessory sheet and brings back the keyboard.">
           Show keyboard
       </message>

chrome/android/features/keyboard_accessory/internal/java/strings/android_keyboard_accessory_strings_grd/IDS_AUTOFILL_KEYBOARD_ACCESSORY_MODERN_CONTENT_DESCRIPTION.png.sha1

+d943c1c4c060f60baed75b91d2e9273302ea7f5c
\ No newline at end of file