diff -r 000000000000 -r 6474c204b198 accessible/src/xul/XULSliderAccessible.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/accessible/src/xul/XULSliderAccessible.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,225 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "XULSliderAccessible.h"
+
+#include "nsAccessibilityService.h"
+#include "Role.h"
+#include "States.h"
+
+#include "nsIFrame.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/FloatingPoint.h"
+
+using namespace mozilla::a11y;
+
+////////////////////////////////////////////////////////////////////////////////
+// XULSliderAccessible
+////////////////////////////////////////////////////////////////////////////////
+
+XULSliderAccessible::
+  XULSliderAccessible(nsIContent* aContent, DocAccessible* aDoc) :
+  AccessibleWrap(aContent, aDoc)
+{
+  mStateFlags |= eHasNumericValue;
+}
+
+// Accessible
+
+role
+XULSliderAccessible::NativeRole()
+{
+  return roles::SLIDER;
+}
+
+uint64_t
+XULSliderAccessible::NativeInteractiveState() const
+ {
+  if (NativelyUnavailable())
+    return states::UNAVAILABLE;
+
+  nsIContent* sliderElm = GetSliderElement();
+  if (sliderElm) {
+    nsIFrame* frame = sliderElm->GetPrimaryFrame();
+    if (frame && frame->IsFocusable())
+      return states::FOCUSABLE;
+  }
+
+  return 0;
+}
+
+bool
+XULSliderAccessible::NativelyUnavailable() const
+{
+  return mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
+                               nsGkAtoms::_true, eCaseMatters);
+}
+
+// nsIAccessible
+
+void
+XULSliderAccessible::Value(nsString& aValue)
+{
+  GetSliderAttr(nsGkAtoms::curpos, aValue);
+}
+
+uint8_t
+XULSliderAccessible::ActionCount()
+{
+  return 1;
+}
+
+NS_IMETHODIMP
+XULSliderAccessible::GetActionName(uint8_t aIndex, nsAString& aName)
+{
+  aName.Truncate();
+
+  NS_ENSURE_ARG(aIndex == 0);
+
+  aName.AssignLiteral("activate");
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+XULSliderAccessible::DoAction(uint8_t aIndex)
+{
+  NS_ENSURE_ARG(aIndex == 0);
+
+  nsIContent* sliderElm = GetSliderElement();
+  if (sliderElm)
+    DoCommand(sliderElm);
+
+  return NS_OK;
+}
+
+double
+XULSliderAccessible::MaxValue() const
+{
+  double value = AccessibleWrap::MaxValue();
+  return IsNaN(value) ? GetSliderAttr(nsGkAtoms::maxpos) : value;
+}
+
+double
+XULSliderAccessible::MinValue() const
+{
+  double value = AccessibleWrap::MinValue();
+  return IsNaN(value) ? GetSliderAttr(nsGkAtoms::minpos) : value;
+}
+
+double
+XULSliderAccessible::Step() const
+{
+  double value = AccessibleWrap::Step();
+  return IsNaN(value) ? GetSliderAttr(nsGkAtoms::increment) : value;
+}
+
+double
+XULSliderAccessible::CurValue() const
+{
+  double value = AccessibleWrap::CurValue();
+  return IsNaN(value) ? GetSliderAttr(nsGkAtoms::curpos) : value;
+}
+
+bool
+XULSliderAccessible::SetCurValue(double aValue)
+{
+  if (AccessibleWrap::SetCurValue(aValue))
+    return true;
+
+  return SetSliderAttr(nsGkAtoms::curpos, aValue);
+}
+
+bool
+XULSliderAccessible::CanHaveAnonChildren()
+{
+  // Do not allow anonymous xul:slider be accessible.
+  return false;
+}
+
+// Utils
+
+nsIContent*
+XULSliderAccessible::GetSliderElement() const
+{
+  if (!mSliderNode) {
+    // XXX: we depend on anonymous content.
+    mSliderNode = mContent->OwnerDoc()->
+      GetAnonymousElementByAttribute(mContent, nsGkAtoms::anonid,
+                                     NS_LITERAL_STRING("slider"));
+  }
+
+  return mSliderNode;
+}
+
+nsresult
+XULSliderAccessible::GetSliderAttr(nsIAtom* aName, nsAString& aValue) const
+{
+  aValue.Truncate();
+
+  if (IsDefunct())
+    return NS_ERROR_FAILURE;
+
+  nsIContent* sliderElm = GetSliderElement();
+  if (sliderElm)
+    sliderElm->GetAttr(kNameSpaceID_None, aName, aValue);
+
+  return NS_OK;
+}
+
+nsresult
+XULSliderAccessible::SetSliderAttr(nsIAtom* aName, const nsAString& aValue)
+{
+  if (IsDefunct())
+    return NS_ERROR_FAILURE;
+
+  nsIContent* sliderElm = GetSliderElement();
+  if (sliderElm)
+    sliderElm->SetAttr(kNameSpaceID_None, aName, aValue, true);
+
+  return NS_OK;
+}
+
+double
+XULSliderAccessible::GetSliderAttr(nsIAtom* aName) const
+{
+  nsAutoString attrValue;
+  nsresult rv = GetSliderAttr(aName, attrValue);
+  if (NS_FAILED(rv))
+    return UnspecifiedNaN<double>();
+
+  nsresult error = NS_OK;
+  double value = attrValue.ToDouble(&error);
+  return NS_FAILED(error) ? UnspecifiedNaN<double>() : value;
+}
+
+bool
+XULSliderAccessible::SetSliderAttr(nsIAtom* aName, double aValue)
+{
+  nsAutoString value;
+  value.AppendFloat(aValue);
+
+  return NS_SUCCEEDED(SetSliderAttr(aName, value));
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+// XULThumbAccessible
+////////////////////////////////////////////////////////////////////////////////
+
+XULThumbAccessible::
+  XULThumbAccessible(nsIContent* aContent, DocAccessible* aDoc) :
+  AccessibleWrap(aContent, aDoc)
+{
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// XULThumbAccessible: Accessible
+
+role
+XULThumbAccessible::NativeRole()
+{
+  return roles::INDICATOR;
+}
+