--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/platform/ScrollbarTheme.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef ScrollbarTheme_h
+#define ScrollbarTheme_h
+
+#include "GraphicsContext.h"
+#include "IntRect.h"
+#include "ScrollTypes.h"
+
+namespace WebCore {
+
+class PlatformMouseEvent;
+class Scrollbar;
+class ScrollView;
+
+class ScrollbarTheme : public Noncopyable {
+public:
+    virtual ~ScrollbarTheme() {};
+
+    virtual bool paint(Scrollbar*, GraphicsContext*, const IntRect& /*damageRect*/) { return false; }
+    virtual ScrollbarPart hitTest(Scrollbar*, const PlatformMouseEvent&) { return NoPart; }
+    
+    virtual int scrollbarThickness(ScrollbarControlSize = RegularScrollbar) { return 0; }
+
+    virtual ScrollbarButtonsPlacement buttonsPlacement() const { return ScrollbarButtonsSingle; }
+
+    virtual bool supportsControlTints() const { return false; }
+
+    virtual void themeChanged() {}
+    
+    virtual bool invalidateOnMouseEnterExit() { return false; }
+
+    void invalidateParts(Scrollbar* scrollbar, ScrollbarControlPartMask mask)
+    {
+        if (mask & BackButtonStartPart)
+            invalidatePart(scrollbar, BackButtonStartPart);
+        if (mask & ForwardButtonStartPart)
+            invalidatePart(scrollbar, ForwardButtonStartPart);
+        if (mask & BackTrackPart)
+            invalidatePart(scrollbar, BackTrackPart);
+        if (mask & ThumbPart)
+            invalidatePart(scrollbar, ThumbPart);
+        if (mask & ForwardTrackPart)
+            invalidatePart(scrollbar, ForwardTrackPart);
+        if (mask & BackButtonEndPart)
+            invalidatePart(scrollbar, BackButtonEndPart);
+        if (mask & ForwardButtonEndPart)
+            invalidatePart(scrollbar, ForwardButtonEndPart);
+    }
+
+    virtual void invalidatePart(Scrollbar*, ScrollbarPart) {}
+
+    virtual void paintScrollCorner(ScrollView*, GraphicsContext* context, const IntRect& cornerRect) { context->fillRect(cornerRect, Color::white, DeviceColorSpace); }
+
+    virtual bool shouldCenterOnThumb(Scrollbar*, const PlatformMouseEvent&) { return false; }
+    virtual bool shouldSnapBackToDragOrigin(Scrollbar*, const PlatformMouseEvent&) { return false; }
+    virtual int thumbPosition(Scrollbar*) { return 0; } // The position of the thumb relative to the track.
+    virtual int thumbLength(Scrollbar*) { return 0; } // The length of the thumb along the axis of the scrollbar.
+    virtual int trackPosition(Scrollbar*) { return 0; } // The position of the track relative to the scrollbar.
+    virtual int trackLength(Scrollbar*) { return 0; } // The length of the track along the axis of the scrollbar.
+
+    virtual int maxOverlapBetweenPages() { return std::numeric_limits<int>::max(); }
+
+    virtual double initialAutoscrollTimerDelay() { return 0.25; }
+    virtual double autoscrollTimerDelay() { return 0.05; }
+
+    virtual void registerScrollbar(Scrollbar*) {}
+    virtual void unregisterScrollbar(Scrollbar*) {}
+
+    static ScrollbarTheme* nativeTheme(); // Must be implemented to return the correct theme subclass.
+};
+
+}
+#endif