1 files changed, 78 insertions, 0 deletions
diff --git a/dom/animation/AnimationTarget.h b/dom/animation/AnimationTarget.h
new file mode 100644
index 000000000..dbfef2e10
--- /dev/null
+++ b/dom/animation/AnimationTarget.h
@@ -0,0 +1,78 @@
+/* -*- 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_AnimationTarget_h
+#define mozilla_AnimationTarget_h
+
+#include "mozilla/Attributes.h"   // For MOZ_NON_OWNING_REF
+#include "mozilla/Maybe.h"
+#include "mozilla/RefPtr.h"
+#include "nsCSSPseudoElements.h"
+
+namespace mozilla {
+
+namespace dom {
+class Element;
+} // namespace dom
+
+struct OwningAnimationTarget
+{
+  OwningAnimationTarget(dom::Element* aElement, CSSPseudoElementType aType)
+    : mElement(aElement), mPseudoType(aType) { }
+
+  explicit OwningAnimationTarget(dom::Element* aElement)
+    : mElement(aElement) { }
+
+  bool operator==(const OwningAnimationTarget& aOther) const
+  {
+     return mElement == aOther.mElement &&
+            mPseudoType == aOther.mPseudoType;
+  }
+
+  // mElement represents the parent element of a pseudo-element, not the
+  // generated content element.
+  RefPtr<dom::Element> mElement;
+  CSSPseudoElementType mPseudoType = CSSPseudoElementType::NotPseudo;
+};
+
+struct NonOwningAnimationTarget
+{
+  NonOwningAnimationTarget(dom::Element* aElement, CSSPseudoElementType aType)
+    : mElement(aElement), mPseudoType(aType) { }
+
+  explicit NonOwningAnimationTarget(const OwningAnimationTarget& aOther)
+    : mElement(aOther.mElement), mPseudoType(aOther.mPseudoType) { }
+
+  // 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;
+};
+
+
+// Helper functions for cycle-collecting Maybe<OwningAnimationTarget>
+inline void
+ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,
+                            Maybe<OwningAnimationTarget>& aTarget,
+                            const char* aName,
+                            uint32_t aFlags = 0)
+{
+  if (aTarget) {
+    ImplCycleCollectionTraverse(aCallback, aTarget->mElement, aName, aFlags);
+  }
+}
+
+inline void
+ImplCycleCollectionUnlink(Maybe<OwningAnimationTarget>& aTarget)
+{
+  if (aTarget) {
+    ImplCycleCollectionUnlink(aTarget->mElement);
+  }
+}
+
+} // namespace mozilla
+
+#endif // mozilla_AnimationTarget_h