Expose public interface for composited selection bounds

public/platform/WebSelectionBound.h

Index: public/platform/WebSelectionBound.h
diff --git a/public/platform/WebSelectionBound.h b/public/platform/WebSelectionBound.h
new file mode 100644
index 0000000000000000000000000000000000000000..ee636d6e5c6051a307f86cff78ed0e6540027c05
--- /dev/null
+++ b/public/platform/WebSelectionBound.h
@@ -0,0 +1,40 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef WebSelectionBound_h
+#define WebSelectionBound_h
+
+#include "public/platform/WebRect.h"
+
+namespace blink {
+
+// An endpoint for an active selection region.
+struct WebSelectionBound {
+    enum Type {
+        Caret,
+        SelectionLeft,
+        SelectionRight
+    };
+
+    explicit WebSelectionBound(Type type)
+        : type(type)
+        , layerId(0)
+    {
+    }
+
+    // The logical type of the endpoint. Note that this is dependent not only on
+    // the bound's relative location, but also the underlying text direction.
+    Type type;
+
+    // The id of the platform layer to which the bound should be anchored.
+    int layerId;
+
+    // The one-dimensional rect of the bound's edge in layer coordinates, not to
+    // be confused with the selection region.
+    WebRect edgeRectInLayer;
+};
+
+} // namespace blink
+
+#endif