Moving GraphicsContext and dependencies from core to platform.

Source/platform/graphics/ImageBuffer.h

Index: Source/platform/graphics/ImageBuffer.h
diff --git a/Source/core/platform/graphics/ImageBuffer.h b/Source/platform/graphics/ImageBuffer.h
similarity index 96%
rename from Source/core/platform/graphics/ImageBuffer.h
rename to Source/platform/graphics/ImageBuffer.h
index 28ef739473f0b889eccedf47cef031ed083d9d59..d247d867935e9e33eb928fc71a8842046b78005c 100644
--- a/Source/core/platform/graphics/ImageBuffer.h
+++ b/Source/platform/graphics/ImageBuffer.h
@@ -28,11 +28,12 @@
 #ifndef ImageBuffer_h
 #define ImageBuffer_h
 
-#include "core/platform/graphics/GraphicsContext.h"
-#include "core/platform/graphics/Canvas2DLayerBridge.h"
+#include "platform/PlatformExport.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/geometry/IntSize.h"
+#include "platform/graphics/Canvas2DLayerBridge.h"
 #include "platform/graphics/ColorSpace.h"
+#include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/GraphicsTypes.h"
 #include "platform/graphics/GraphicsTypes3D.h"
 #include "platform/transforms/AffineTransform.h"
@@ -81,7 +82,7 @@ enum OpacityMode {
     Opaque,
 };
 
-class ImageBuffer {
+class PLATFORM_EXPORT ImageBuffer {
     WTF_MAKE_NONCOPYABLE(ImageBuffer); WTF_MAKE_FAST_ALLOCATED;
 public:
     // Will return a null pointer on allocation failure.
@@ -167,7 +168,7 @@ struct ImageDataBuffer {
     RefPtr<Uint8ClampedArray> m_data;
 };
 
-String ImageDataToDataURL(const ImageDataBuffer&, const String& mimeType, const double* quality);
+String PLATFORM_EXPORT ImageDataToDataURL(const ImageDataBuffer&, const String& mimeType, const double* quality);
 
 } // namespace WebCore