Media Controls a11y: add text/description/role to more controls components.

content/child/blink_platform_impl.cc

Index: content/child/blink_platform_impl.cc
diff --git a/content/child/blink_platform_impl.cc b/content/child/blink_platform_impl.cc
index b02630358357766d44b5b840c59dd888a1f5e8ce..791766602ffa4e88444a5c6fcb3264eef72e5a25 100644
--- a/content/child/blink_platform_impl.cc
+++ b/content/child/blink_platform_impl.cc
@@ -146,6 +146,10 @@ static int ToMessageID(WebLocalizedString::Name name) {
       return IDS_AX_MEDIA_CAST_OFF_BUTTON;
     case WebLocalizedString::AxMediaCastOnButton:
       return IDS_AX_MEDIA_CAST_ON_BUTTON;
+    case WebLocalizedString::AxMediaDownloadButton:
+      return IDS_AX_MEDIA_DOWNLOAD_BUTTON;
+    case WebLocalizedString::AxMediaOverflowButton:
+      return IDS_AX_MEDIA_OVERFLOW_BUTTON;
     case WebLocalizedString::AXMediaAudioElementHelp:
       return IDS_AX_MEDIA_AUDIO_ELEMENT_HELP;
     case WebLocalizedString::AXMediaVideoElementHelp:
@@ -182,6 +186,10 @@ static int ToMessageID(WebLocalizedString::Name name) {
       return IDS_AX_MEDIA_CAST_OFF_BUTTON_HELP;
     case WebLocalizedString::AxMediaCastOnButtonHelp:
       return IDS_AX_MEDIA_CAST_ON_BUTTON_HELP;
+    case WebLocalizedString::AxMediaDownloadButtonHelp:
+      return IDS_AX_MEDIA_DOWNLOAD_BUTTON_HELP;
+    case WebLocalizedString::AxMediaOverflowButtonHelp:
+      return IDS_AX_MEDIA_OVERFLOW_BUTTON_HELP;
     case WebLocalizedString::AXMillisecondFieldText:
       return IDS_AX_MILLISECOND_FIELD_TEXT;
     case WebLocalizedString::AXMinuteFieldText:
@@ -244,8 +252,6 @@ static int ToMessageID(WebLocalizedString::Name name) {
       return IDS_FORM_OTHER_TIME_LABEL;
     case WebLocalizedString::OtherWeekLabel:
       return IDS_FORM_OTHER_WEEK_LABEL;
-    case WebLocalizedString::AxMediaOverflowButton:
-      return IDS_AX_MEDIA_OVERFLOW_BUTTON;
     case WebLocalizedString::OverflowMenuCaptions:
       return IDS_MEDIA_OVERFLOW_MENU_CLOSED_CAPTIONS;
     case WebLocalizedString::OverflowMenuCast: