Moving GraphicsContext and dependencies from core to platform.

Source/platform/graphics/Image.h

Index: Source/platform/graphics/Image.h
diff --git a/Source/core/platform/graphics/Image.h b/Source/platform/graphics/Image.h
similarity index 97%
rename from Source/core/platform/graphics/Image.h
rename to Source/platform/graphics/Image.h
index ad5c42f4ac174df64b2584dfd8755753effe3950..0ab5cad0cdfea33edcabc65d79901aa95dc437a4 100644
--- a/Source/core/platform/graphics/Image.h
+++ b/Source/platform/graphics/Image.h
@@ -27,11 +27,12 @@
 #ifndef Image_h
 #define Image_h
 
-#include "core/platform/graphics/skia/NativeImageSkia.h"
+#include "platform/PlatformExport.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/Color.h"
 #include "platform/graphics/GraphicsTypes.h"
 #include "platform/graphics/ImageOrientation.h"
+#include "platform/graphics/skia/NativeImageSkia.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
@@ -51,7 +52,7 @@ class SharedBuffer;
 // This class gets notified when an image creates or destroys decoded frames and when it advances animation frames.
 class ImageObserver;
 
-class Image : public RefCounted<Image> {
+class PLATFORM_EXPORT Image : public RefCounted<Image> {
     friend class GeneratedImage;
     friend class CrossfadeGeneratedImage;
     friend class GradientGeneratedImage;