Add m-esr52 at 52.6.0

1 files changed, 57 insertions, 0 deletions

diff --git a/layout/generic/SelectionChangeListener.h b/layout/generic/SelectionChangeListener.h
new file mode 100644
index 000000000..81d66aeb4
--- /dev/null
+++ b/layout/generic/SelectionChangeListener.h
@@ -0,0 +1,57 @@
+/* -*- 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/. */
+
+#ifndef mozilla_SelectionChangeListener_h_
+#define mozilla_SelectionChangeListener_h_
+
+#include "nsISelectionListener.h"
+#include "nsISelectionPrivate.h"
+#include "mozilla/Attributes.h"
+
+namespace mozilla {
+namespace dom {
+
+class SelectionChangeListener final : public nsISelectionListener
+{
+public:
+  // SelectionChangeListener has to participate in cycle collection because
+  // it holds strong references to nsINodes in its mOldRanges array.
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_CLASS(SelectionChangeListener)
+  NS_DECL_NSISELECTIONLISTENER
+
+  // This field is used to keep track of the ranges which were present in the
+  // selection when the selectionchange event was previously fired. This allows
+  // for the selectionchange event to only be fired when a selection is actually
+  // changed.
+  struct RawRangeData
+  {
+    // These properties are not void*s to avoid the potential situation where the
+    // nsINode is freed, and a new nsINode is allocated with the same address, which
+    // could potentially break the comparison logic. In reality, this is extremely
+    // unlikely to occur (potentially impossible), but these nsCOMPtrs are safer.
+    // They are never dereferenced.
+    nsCOMPtr<nsINode> mStartParent;
+    nsCOMPtr<nsINode> mEndParent;
+
+    // XXX These are int32_ts on nsRange, but uint32_ts in the return value
+    // of GetStart_, so I use uint32_ts here. See bug 1194256.
+    uint32_t mStartOffset;
+    uint32_t mEndOffset;
+
+    explicit RawRangeData(const nsRange* aRange);
+    bool Equals(const nsRange* aRange);
+  };
+
+private:
+  nsTArray<RawRangeData> mOldRanges;
+
+  ~SelectionChangeListener() {}
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_SelectionChangeListener_h_