Maintain SkPaint in GraphicsContextState.

Source/platform/graphics/CrossfadeGeneratedImage.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 48 matching lines @@
     context->clip(IntRect(IntPoint(), m_crossfadeSize));
     context->beginTransparencyLayer(1);
 
     // Draw the image we're fading away from.
     context->save();
     if (m_crossfadeSize != fromImageSize) {
         context->scale(FloatSize(
             static_cast<float>(m_crossfadeSize.width()) / fromImageSize.width(),
             static_cast<float>(m_crossfadeSize.height()) / fromImageSize.height()));
     }
-    context->setAlpha(inversePercentage);
+    context->setAlphaAsFloat(inversePercentage);
     context->drawImage(m_fromImage, IntPoint());
     context->restore();
 
     // Draw the image we're fading towards.
     context->save();
     if (m_crossfadeSize != toImageSize) {
         context->scale(FloatSize(
             static_cast<float>(m_crossfadeSize.width()) / toImageSize.width(),
             static_cast<float>(m_crossfadeSize.height()) / toImageSize.height()));
     }
-    context->setAlpha(m_percentage);
+    context->setAlphaAsFloat(m_percentage);
     context->drawImage(m_toImage, IntPoint(), CompositePlusLighter);
     context->restore();
 
     context->endLayer();
 }
 
 void CrossfadeGeneratedImage::draw(GraphicsContext* context, const FloatRect& dstRect, const FloatRect& srcRect, CompositeOperator compositeOp, blink::WebBlendMode blendMode)
 {
     GraphicsContextStateSaver stateSaver(*context);
     context->setCompositeOperation(compositeOp, blendMode);
@@ skipping 14 matching lines @@
 
     // Fill with the cross-faded image.
     GraphicsContext* graphicsContext = imageBuffer->context();
     drawCrossfade(graphicsContext);
 
     // Tile the image buffer into the context.
     imageBuffer->drawPattern(context, srcRect, scale, phase, compositeOp, dstRect, blendMode, repeatSpacing);
 }
 
 }