Move paint code for RenderScrollbar and RenderScrollbarPart into ScrollbarPainter.

Source/core/paint/ScrollbarPainter.cpp

+// 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.
+
+#include "config.h"
+#include "core/paint/ScrollbarPainter.h"
+
+#include "core/paint/BlockPainter.h"
+#include "core/rendering/PaintInfo.h"
+#include "core/rendering/RenderScrollbar.h"
+#include "core/rendering/RenderScrollbarPart.h"
+#include "platform/graphics/GraphicsContext.h"
+namespace blink {
+
+void ScrollbarPainter::paintPart(GraphicsContext* graphicsContext, ScrollbarPart partType, const IntRect& rect)
+{
+    RenderScrollbarPart* partRenderer = m_renderScrollbar.getPart(partType);
+    if (!partRenderer)
+        return;
+    paintIntoRect(partRenderer, graphicsContext, m_renderScrollbar.location(), rect);
+}
+
+void ScrollbarPainter::paintIntoRect(RenderScrollbarPart* renderScrollbarPart, GraphicsContext* graphicsContext, const LayoutPoint& paintOffset, const LayoutRect& rect)
+{
+    // Make sure our dimensions match the rect.
+    // FIXME: Setting these is a bad layering violation!
+    renderScrollbarPart->setLocation(rect.location() - toSize(paintOffset));
+    renderScrollbarPart->setWidth(rect.width());
+    renderScrollbarPart->setHeight(rect.height());
+
+    // Now do the paint.
+    PaintInfo paintInfo(graphicsContext, pixelSnappedIntRect(rect), PaintPhaseBlockBackground, PaintBehaviorNormal);
+    BlockPainter blockPainter(*renderScrollbarPart);
+    blockPainter.paint(paintInfo, paintOffset);
+    paintInfo.phase = PaintPhaseChildBlockBackgrounds;
+    blockPainter.paint(paintInfo, paintOffset);
+    paintInfo.phase = PaintPhaseFloat;
+    blockPainter.paint(paintInfo, paintOffset);
+    paintInfo.phase = PaintPhaseForeground;
+    blockPainter.paint(paintInfo, paintOffset);
+    paintInfo.phase = PaintPhaseOutline;
+    blockPainter.paint(paintInfo, paintOffset);
+}
+
+} // namespace blink