a11y/Mac: Add screenreader support for SubtleNotificationView announcements.

chrome/browser/ui/views/new_back_shortcut_bubble.cc

Index: chrome/browser/ui/views/new_back_shortcut_bubble.cc
diff --git a/chrome/browser/ui/views/new_back_shortcut_bubble.cc b/chrome/browser/ui/views/new_back_shortcut_bubble.cc
index 21a62386cd9929edb22c869ebb05ce37e440ecf2..defd768c6ed52980b680cb8b53ea21e561b7257c 100644
--- a/chrome/browser/ui/views/new_back_shortcut_bubble.cc
+++ b/chrome/browser/ui/views/new_back_shortcut_bubble.cc
@@ -62,14 +62,22 @@ void NewBackShortcutBubble::UpdateContent(bool forward) {
 #if defined(OS_MACOSX)
   // U+2318 = PLACE OF INTEREST SIGN (Mac Command symbol).
   base::string16 accelerator = base::WideToUTF16(L"\x2318");
+  base::string16 accessible_accelerator =
+      l10n_util::GetStringUTF16(IDS_MAC_COMMAND_KEY_DESCRIPTION);
 #else
   base::string16 accelerator = l10n_util::GetStringUTF16(IDS_APP_ALT_KEY);
+  base::string16 accessible_accelerator = accelerator;
 #endif
 
   int message_id = forward ? IDS_PRESS_ALT_RIGHT_TO_GO_FORWARD
                            : IDS_PRESS_ALT_LEFT_TO_GO_BACK;
   // U+2192 = RIGHTWARDS ARROW; U+2190 = LEFTWARDS ARROW.
   base::string16 arrow_key = base::WideToUTF16(forward ? L"\x2192" : L"\x2190");
+  base::string16 accessible_arrow_key =
+      forward ? l10n_util::GetStringUTF16(IDS_APP_RIGHT_ARROW_KEY)
+              : l10n_util::GetStringUTF16(IDS_APP_LEFT_ARROW_KEY);
+  view_->SetAccessibleName(l10n_util::GetStringFUTF16(
+      message_id, accessible_accelerator, accessible_arrow_key));
   view_->UpdateContent(
       l10n_util::GetStringFUTF16(message_id, accelerator, arrow_key),
       base::string16());