Bug 1321284 - Crash in nsCSSFrameConstructor::GetInsertionPrevSibling when trying to reframe native anonymous content

* Make StyleChildrenIterator skip NAC generated by root element primary frame ancestors.
* Add nsINode::GetFlattenedTreeParentNodeForStyle.
* Add iterator class to find all restyle roots.

NOTE: Parts 1, 2, and "4.2"

Tag #1375

1 files changed, 37 insertions, 0 deletions

diff --git a/layout/style/DocumentStyleRootIterator.h b/layout/style/DocumentStyleRootIterator.h
new file mode 100644
index 000000000..7dcdc7fa1
--- /dev/null
+++ b/layout/style/DocumentStyleRootIterator.h
@@ -0,0 +1,37 @@
+/* -*- 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 DocumentStyleRootIterator_h
+#define DocumentStyleRootIterator_h
+
+#include "nsTArray.h"
+
+class nsIContent;
+class nsIDocument;
+
+namespace mozilla {
+
+/**
+ * DocumentStyleRootIterator traverses the roots of the document from the
+ * perspective of the Servo-backed style system.  This will first traverse
+ * the document root, followed by any document level native anonymous content.
+ */
+class DocumentStyleRootIterator
+{
+public:
+  explicit DocumentStyleRootIterator(nsIDocument* aDocument);
+  ~DocumentStyleRootIterator() { MOZ_COUNT_DTOR(DocumentStyleRootIterator); }
+
+  Element* GetNextStyleRoot();
+
+private:
+  AutoTArray<nsIContent*, 8> mStyleRoots;
+  uint32_t mPosition;
+};
+
+} // namespace mozilla
+
+#endif // DocumentStyleRootIterator_h