Implement canvas2d direction attribute

Source/core/html/canvas/CanvasRenderingContext2D.h

Index: Source/core/html/canvas/CanvasRenderingContext2D.h
diff --git a/Source/core/html/canvas/CanvasRenderingContext2D.h b/Source/core/html/canvas/CanvasRenderingContext2D.h
index 6eba5f5b313772a10a5e9c24f1d7f6c3be305281..64591239ac3c64b0fdcaeabaec8aa1676f32d9a5 100644
--- a/Source/core/html/canvas/CanvasRenderingContext2D.h
+++ b/Source/core/html/canvas/CanvasRenderingContext2D.h
@@ -39,6 +39,7 @@
 #include "platform/graphics/GraphicsTypes.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/Path.h"
+#include "platform/text/TextDirection.h"
 #include "platform/transforms/AffineTransform.h"
 #include "wtf/HashMap.h"
 #include "wtf/Vector.h"
@@ -211,6 +212,9 @@ public:
     String textBaseline() const;
     void setTextBaseline(const String&);
 
+    String direction() const;
+    void setDirection(const String&);
+
     void fillText(const String& text, float x, float y);
     void fillText(const String& text, float x, float y, float maxWidth);
     void strokeText(const String& text, float x, float y);
@@ -279,6 +283,7 @@ private:
         // Text state.
         TextAlign m_textAlign;
         TextBaseline m_textBaseline;
+        TextDirection m_direction;
 
         String m_unparsedFont;
         Font m_font;