Add support for new canvas ellipse method.

Source/core/html/canvas/CanvasRenderingContext2D.idl

Index: Source/core/html/canvas/CanvasRenderingContext2D.idl
diff --git a/Source/core/html/canvas/CanvasRenderingContext2D.idl b/Source/core/html/canvas/CanvasRenderingContext2D.idl
index 3c2337b0627a6e8471eb809b2bd8455b4d44ff10..625e44ebb15ef3c29846692b09a231bef551eb07 100644
--- a/Source/core/html/canvas/CanvasRenderingContext2D.idl
+++ b/Source/core/html/canvas/CanvasRenderingContext2D.idl
@@ -76,6 +76,7 @@ interface CanvasRenderingContext2D : CanvasRenderingContext {
     [RaisesException] void arcTo(float x1, float y1, float x2, float y2, float radius);
     void rect(float x, float y, float width, float height);
     [RaisesException] void arc(float x, float y, float radius, float startAngle, float endAngle, [Default=Undefined] optional boolean anticlockwise);
+    [RaisesException] void ellipse(float x, float y, float radiusX, float radiusY, float rotation, float startAngle, float endAngle, boolean anticlockwise);
 
     void fill(optional CanvasWindingRule winding);
     void stroke();