Bug 1425769 - Base class for ShadowRoot and Document to manage style state

Tag #1375

dom/base/StyleScope.h

@@ -0,0 +1,81 @@
+/* -*- 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_dom_StyleScope_h__
+#define mozilla_dom_StyleScope_h__
+
+#include "nsTArray.h"
+
+class nsINode;
+
+namespace mozilla {
+class StyleSheet;
+
+namespace dom {
+
+class StyleSheetList;
+
+/**
+ * A class meant to be shared by ShadowRoot and Document, that holds a list of
+ * stylesheets.
+ *
+ * TODO(emilio, bug 1418159): In the future this should hold most of the
+ * relevant style state, this should allow us to fix bug 548397.
+ */
+class StyleScope
+{
+public:
+  virtual nsINode& AsNode() = 0;
+
+  const nsINode& AsNode() const
+  {
+    return const_cast<StyleScope&>(*this).AsNode();
+  }
+
+  StyleSheet* SheetAt(size_t aIndex) const
+  {
+    return mStyleSheets.SafeElementAt(aIndex);
+  }
+
+  size_t SheetCount() const
+  {
+    return mStyleSheets.Length();
+  }
+
+  int32_t IndexOfSheet(const StyleSheet& aSheet) const
+  {
+    return mStyleSheets.IndexOf(&aSheet);
+  }
+
+  void InsertSheetAt(size_t aIndex, StyleSheet& aSheet)
+  {
+    mStyleSheets.InsertElementAt(aIndex, &aSheet);
+  }
+
+  void RemoveSheet(StyleSheet& aSheet)
+  {
+    mStyleSheets.RemoveElement(&aSheet);
+  }
+
+  void AppendStyleSheet(StyleSheet& aSheet)
+  {
+    mStyleSheets.AppendElement(&aSheet);
+  }
+
+  StyleSheetList& EnsureDOMStyleSheets();
+
+  ~StyleScope();
+
+protected:
+  nsTArray<RefPtr<mozilla::StyleSheet>> mStyleSheets;
+  RefPtr<mozilla::dom::StyleSheetList> mDOMStyleSheets;
+};
+
+}
+
+}
+
+#endif