Bug 1249219 - Part 1: Define NonOwningAnimationTarget. r=birtles

NonOwningAnimationTarget is a struct made of two members:
1. mozilla::dom::Element*
2. mozilla::CSSPseudoElementType

--HG--
extra : rebase_source : df7ecf192c14f1973b064ffe8a31618df2e6955d

dom/animation/NonOwningAnimationTarget.h

@@ -0,0 +1,32 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_NonOwningAnimationTarget_h
+#define mozilla_NonOwningAnimationTarget_h
+
+#include "mozilla/Attributes.h"   // For MOZ_NON_OWNING_REF
+#include "nsCSSPseudoElements.h"
+
+namespace mozilla {
+
+namespace dom {
+class Element;
+} // namespace dom
+
+struct NonOwningAnimationTarget
+{
+  NonOwningAnimationTarget(dom::Element* aElement, CSSPseudoElementType aType)
+    : mElement(aElement), mPseudoType(aType) { }
+
+  // mElement represents the parent element of a pseudo-element, not the
+  // generated content element.
+  dom::Element* MOZ_NON_OWNING_REF mElement = nullptr;
+  CSSPseudoElementType mPseudoType = CSSPseudoElementType::NotPseudo;
+};
+
+} // namespace mozilla
+
+#endif // mozilla_NonOwningAnimationTarget_h

dom/animation/moz.build

@@ -26,6 +26,7 @@ EXPORTS.mozilla += [
     'ComputedTimingFunction.h',
     'EffectCompositor.h',
     'EffectSet.h',
+    'NonOwningAnimationTarget.h',
     'PendingAnimationTracker.h',
     'PseudoElementHashEntry.h',
     'TimingParams.h',