--- a/layout/forms/nsGfxCheckboxControlFrame.cpp
+++ b/layout/forms/nsGfxCheckboxControlFrame.cpp
@@ -42,8 +42,27 @@ nsGfxCheckboxControlFrame::~nsGfxCheckbo
 
 #ifdef ACCESSIBILITY
 a11y::AccType
 nsGfxCheckboxControlFrame::AccessibleType()
 {
   return a11y::eHTMLCheckboxType;
 }
 #endif
+
+//------------------------------------------------------------
+bool
+nsGfxCheckboxControlFrame::IsChecked()
+{
+  nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
+  bool retval = false;
+  elem->GetChecked(&retval);
+  return retval;
+}
+
+bool
+nsGfxCheckboxControlFrame::IsIndeterminate()
+{
+  nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
+  bool retval = false;
+  elem->GetIndeterminate(&retval);
+  return retval;
+}

--- a/layout/forms/nsGfxCheckboxControlFrame.h
+++ b/layout/forms/nsGfxCheckboxControlFrame.h
@@ -20,12 +20,17 @@ public:
   virtual nsresult GetFrameName(nsAString& aResult) const override {
     return MakeFrameName(NS_LITERAL_STRING("CheckboxControl"), aResult);
   }
 #endif
 
 #ifdef ACCESSIBILITY
   virtual mozilla::a11y::AccType AccessibleType() override;
 #endif
+
+protected:
+
+  bool IsChecked();
+  bool IsIndeterminate();
 };
 
 #endif