Implement media cast buttons

Source/core/accessibility/AXMediaControls.cpp

Index: Source/core/accessibility/AXMediaControls.cpp
diff --git a/Source/core/accessibility/AXMediaControls.cpp b/Source/core/accessibility/AXMediaControls.cpp
index 866f360afe2c25be79dabd4dd547cbd9a6869734..3f2b79ce6efd16d15d9d3ef71805ccdf174390f2 100644
--- a/Source/core/accessibility/AXMediaControls.cpp
+++ b/Source/core/accessibility/AXMediaControls.cpp
@@ -112,6 +112,10 @@ String AccessibilityMediaControl::accessibilityDescription() const
         return queryString(WebLocalizedString::AXMediaShowClosedCaptionsButton);
     case MediaHideClosedCaptionsButton:
         return queryString(WebLocalizedString::AXMediaHideClosedCaptionsButton);
+    case MediaCastOffButton:
+        return queryString(WebLocalizedString::AxMediaCastOffButton);
+    case MediaCastOnButton:
+        return queryString(WebLocalizedString::AxMediaCastOnButton);
     default:
         return queryString(WebLocalizedString::AXMediaDefault);
     }
@@ -142,6 +146,10 @@ String AccessibilityMediaControl::helpText() const
         return queryString(WebLocalizedString::AXMediaShowClosedCaptionsButtonHelp);
     case MediaHideClosedCaptionsButton:
         return queryString(WebLocalizedString::AXMediaHideClosedCaptionsButtonHelp);
+    case MediaCastOffButton:
+        return queryString(WebLocalizedString::AxMediaCastOffButtonHelp);
+    case MediaCastOnButton:
+        return queryString(WebLocalizedString::AxMediaCastOnButtonHelp);
     default:
         return queryString(WebLocalizedString::AXMediaDefault);
     }