Move SVG container paint code to SVGContainerPainter

Source/core/paint/SVGContainerPainter.h

+// 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 SVGContainerPainter_h
+#define SVGContainerPainter_h
+
+namespace blink {
+
+struct PaintInfo;
+class RenderSVGContainer;
+
+class SVGContainerPainter {
+public:
+    SVGContainerPainter(RenderSVGContainer& renderSVGContainer) : m_renderSVGContainer(renderSVGContainer) { }
+
+    void paint(PaintInfo&);
+
+private:
+    RenderSVGContainer& m_renderSVGContainer;
+};
+
+} // namespace blink
+
+#endif // SVGContainerPainter_h