Moving GraphicsContext and dependencies from core to platform.

Source/platform/scroll/ScrollbarThemeMacOverlayAPI.h

Index: Source/platform/scroll/ScrollbarThemeMacOverlayAPI.h
diff --git a/Source/core/platform/ScrollbarThemeMacOverlayAPI.h b/Source/platform/scroll/ScrollbarThemeMacOverlayAPI.h
similarity index 95%
rename from Source/core/platform/ScrollbarThemeMacOverlayAPI.h
rename to Source/platform/scroll/ScrollbarThemeMacOverlayAPI.h
index b0c5aef9eb70ec79fb83c8014178976ec469e31b..c9056ac17b5f1af01f957e05ead192fd3a792649 100644
--- a/Source/core/platform/ScrollbarThemeMacOverlayAPI.h
+++ b/Source/platform/scroll/ScrollbarThemeMacOverlayAPI.h
@@ -31,13 +31,13 @@
 #ifndef ScrollbarThemeMacOverlayAPI_h
 #define ScrollbarThemeMacOverlayAPI_h
 
-#include "core/platform/ScrollbarThemeMacCommon.h"
+#include "platform/scroll/ScrollbarThemeMacCommon.h"
 
 typedef id ScrollbarPainter;
 
 namespace WebCore {
 
-class ScrollbarThemeMacOverlayAPI : public ScrollbarThemeMacCommon {
+class PLATFORM_EXPORT ScrollbarThemeMacOverlayAPI : public ScrollbarThemeMacCommon {
 public:
     virtual void updateEnabledState(ScrollbarThemeClient*) OVERRIDE;
     virtual int scrollbarThickness(ScrollbarControlSize = RegularScrollbar) OVERRIDE;