Removing the dependency on GraphicsContext for drawing images in 2D canvas

Source/platform/graphics/skia/SkiaUtils.h

Index: Source/platform/graphics/skia/SkiaUtils.h
diff --git a/Source/platform/graphics/skia/SkiaUtils.h b/Source/platform/graphics/skia/SkiaUtils.h
index f0372ae22414ae02e762cbb7e7d86f351aede557..181bce0b17356946749e236348e27da008820390 100644
--- a/Source/platform/graphics/skia/SkiaUtils.h
+++ b/Source/platform/graphics/skia/SkiaUtils.h
@@ -127,8 +127,6 @@ InterpolationQuality computeInterpolationQuality(
     float destHeight,
     bool isDataComplete = true);
 
-bool shouldDrawAntiAliased(const GraphicsContext*, const SkRect& destRect);
-
 // This replicates the old skia behavior when it used to take radius for blur. Now it takes sigma.
 inline SkScalar skBlurRadiusToSigma(SkScalar radius)
 {
@@ -136,6 +134,33 @@ inline SkScalar skBlurRadiusToSigma(SkScalar radius)
     return 0.288675f * radius + 0.5f;
 }
 
+template<typename DrawFunc>
+void drawPlatformFocusRing(const DrawFunc& drawFunc, SkColor color, int width)

[Stephen White, 2015/05/29 17:26:37]

It looks like the two call sites which draw focus rings as paths provide almost
identical lambdas.

Rather than exposing the functor as an API here, could we provide two functions
here in SkiaUtils (drawPlatformFocusRingPath and drawPlatformFocusRingRect)
which use a lambda internally if necessary?

+{
+    SkPaint paint;
+    paint.setAntiAlias(true);
+    paint.setStyle(SkPaint::kStroke_Style);
+    paint.setColor(color);
+
+#if OS(MACOSX)
+    paint.setStrokeWidth(width);
+    paint.setAlpha(64);
+    float cornerRadius = (width - 1) * 0.5f;
+#else
+    paint.setStrokeWidth(1);
+    const float cornerRadius = 1;
+#endif
+
+    drawFunc(paint, cornerRadius);
+
+#if OS(MACOSX)
+    // Inner part
+    paint.setAlpha(128);
+    paint.setStrokeWidth(paint.getStrokeWidth() * 0.5f);
+    drawFunc(paint, cornerRadius);
+#endif
+}
+
 } // namespace blink
 
 #endif  // SkiaUtils_h